rodinia-benchmark/opencl/b+tree/main.c

// # ifdef __cplusplus
// extern "C" {
// # endif

//========================================================================================================================================================================================================200
//======================================================================================================================================================150
//====================================================================================================100
//==================================================50

//========================================================================================================================================================================================================200
//	INFORMATION
//========================================================================================================================================================================================================200

//======================================================================================================================================================150
//	UPDATE
//======================================================================================================================================================150

// 2009; Amittai Aviram; entire code written in C; 
// 2010; Jordan Fix and Andrew Wilkes; code converted to CUDA; 
// 2011.10; Lukasz G. Szafaryn; code converted to portable form, to C, OpenMP, CUDA, PGI versions; 
// 2011.12; Lukasz G. Szafaryn; Split different versions for Rodinia.
// 2011.12; Lukasz G. Szafaryn; code converted to OpenCL;

//======================================================================================================================================================150
//	DESCRIPTION
//======================================================================================================================================================150

// Description

//======================================================================================================================================================150
//	USE
//======================================================================================================================================================150

// EXAMPLE:
// ./a.out -file ./input/mil.txt
// ...then enter any of the following commands after the prompt > :
// f <x>  -- Find the value under key <x>
// p <x> -- Print the path from the root to key k and its associated value
// t -- Print the B+ tree
// l -- Print the keys of the leaves (bottom row of the tree)
// v -- Toggle output of pointer addresses ("verbose") in tree and leaves.
// k <x> -- Run <x> bundled queries on the CPU and GPU (B+Tree) (Selects random values for each search)
// j <x> <y> -- Run a range search of <x> bundled queries on the CPU and GPU (B+Tree) with the range of each search of size <y>
// x <z> -- Run a single search for value z on the GPU and CPU
// y <a> <b> -- Run a single range search for range a-b on the GPU and CPU
// q -- Quit. (Or use Ctl-D.)

//======================================================================================================================================================150
//	END
//======================================================================================================================================================150

//========================================================================================================================================================================================================200
//	DEFINE/INCLUDE
//========================================================================================================================================================================================================200

//======================================================================================================================================================150
//	LIBRARIES
//======================================================================================================================================================150

#include <stdio.h>									// (in directory known to compiler)			needed by printf, stderr
#include <limits.h>									// (in directory known to compiler)			needed by INT_MIN, INT_MAX
// #include <sys/time.h>							// (in directory known to compiler)			needed by ???
#include <math.h>									// (in directory known to compiler)			needed by log, pow
#include <string.h>									// (in directory known to compiler)			needed by memset

//======================================================================================================================================================150
//	COMMON
//======================================================================================================================================================150

#include "./common.h"								// (in directory provided here)

//======================================================================================================================================================150
//	DEFINE
//======================================================================================================================================================150

//======================================================================================================================================================150
//	UTILITIES
//======================================================================================================================================================150

#include "./util/timer/timer.h"						// (in directory provided here)
#include "./util/num/num.h"							// (in directory provided here)

//======================================================================================================================================================150
//	KERNEL HEADERS
//======================================================================================================================================================150

#include "./kernel/kernel_gpu_opencl_wrapper.h"		// (in directory provided here)
#include "./kernel/kernel_gpu_opencl_wrapper_2.h"		// (in directory provided here)

//======================================================================================================================================================150
//	HEADER
//======================================================================================================================================================150

#include "./main.h"									// (in directory provided here)

//======================================================================================================================================================150
//	END
//======================================================================================================================================================150

//========================================================================================================================================================================================================200
//	VARIABLES
//========================================================================================================================================================================================================200

// general variables
knode *knodes;
record *krecords;
char *mem;
long freeptr;
long malloc_size;
long size;
long maxheight;

/* The order determines the maximum and minimum
* number of entries (keys and pointers) in any
* node.  Every node has at most order - 1 keys and
* at least (roughly speaking) half that number.
* Every leaf has as many pointers to data as keys,
* and every internal node has one more pointer
* to a subtree than the number of keys.
* This global variable is initialized to the
* default value.
*/
int order = DEFAULT_ORDER;

/* The queue is used to print the tree in
* level order, starting from the root
* printing each entire rank on a separate
* line, finishing with the leaves.
*/
node *queue = NULL;

/* The user can toggle on and off the "verbose"
* property, which causes the pointer addresses
* to be printed out in hexadecimal notation
* next to their corresponding keys.
*/
bool verbose_output = false;

//========================================================================================================================================================================================================200
//	FUNCTIONS
//========================================================================================================================================================================================================200

//======================================================================================================================================================150
//	Components
//======================================================================================================================================================150

void 
list_init(	list_t *l,
			int32_t (*compare)(const void *key, 
			const void *with),
			void (*datum_delete)(void *))
{
  l->head = l->tail = NULL;
  l->length = 0;
  l->compare = compare;
  l->datum_delete = datum_delete;
}

void 
list_delete(list_t *l)
{

  list_item_t *li, *del;

  for (li = l->head; li;) {

    del = li;
    li = li->next;
    list_item_delete(del, l->datum_delete);
  }

  l->head = l->tail = NULL;
  l->length = 0;
}

void 
list_reset(list_t *l)
{
  list_delete(l);
}

void 
list_insert_item_head(	list_t *l, 
						list_item_t *i)
{
  if (l->head) {
    i->next = l->head;
    l->head->pred = i;
    l->head = i;
    l->head->pred = NULL;
  } else {
    l->head = l->tail = i;
    i->next = i->pred = NULL;
  }
  l->length++;
}

void 
list_insert_item_tail(	list_t *l, 
						list_item_t *i)
{
  if (l->head) {
    l->tail->next = i;
    i->pred = l->tail;
    i->next = NULL;
    l->tail = i;
  } else {
    l->head = l->tail = i;
    i->next = i->pred = NULL;
  }
  l->length++;
}

void 
list_insert_item_before(list_t *l, 
						list_item_t *next, 
						list_item_t *i)
{
  /* Assume next is actually in the list! */
  /* If it's not, we may lose the list.   */
  if (l->head == next) {
    i->next = next;
    i->pred = NULL;
    l->head = i;
    next->pred = i;
  } else {
    i->next = next;
    i->pred = next->pred;
    next->pred->next = i;
    next->pred = i;
  }
  l->length++;
}

void 
list_insert_item_after(	list_t *l, 
						list_item_t *pred, 
						list_item_t *i)
{
  /* Assume pred is actually in the list! */
  /* If it's not, we may lose the list.   */
  if (l->tail == pred) {
    i->pred = pred;
    i->next = NULL;
    l->tail = i;
    pred->next = i;
  } else {
    i->pred = pred;
    i->next = pred->next;
    pred->next->pred = i;
    pred->next = i;
  }
  l->length++;
}

void 
list_insert_item_sorted(list_t *l, 
						list_item_t *i)
{
  list_item_t *itr;

  if (l->head) {
    for (itr = l->head; itr && l->compare(list_item_get_datum(i),
					  list_item_get_datum(itr)) < 0;
	 itr = itr->next)
      ;
    if (itr) {
      i->next = itr;
      i->pred = itr->pred;
      itr->pred = i;
      i->pred->next = i;
    } else {
      l->tail->next = i;
      i->pred = l->tail;
      i->next = NULL;
      l->tail = i;
    }
  } else {
    l->head = l->tail = i;
    i->pred = i->next = NULL;
  }
  l->length++;
}

void 
list_insert_head(	list_t *l, 
					void *v)
{
  list_item_t *i;
  i = (list_item_t *)malloc(sizeof (*i));
  list_item_init(i, v);
  if (l->head) {
    i->next = l->head;
    l->head->pred = i;
    l->head = i;
    l->head->pred = NULL;
  } else {
    l->head = l->tail = i;
    i->next = i->pred = NULL;
  }
  l->length++;

}

void 
list_insert_tail(	list_t *l, 
					void *v)
{
  list_item_t *i;

  i = (list_item_t *)malloc(sizeof (*i));
  list_item_init(i, v);
  if (l->head) {
    l->tail->next = i;
    i->pred = l->tail;
    i->next = NULL;
    l->tail = i;
  } else {
    l->head = l->tail = i;
    i->next = i->pred = NULL;
  }
  l->length++;
}

void 
list_insert_before(	list_t *l, 
					list_item_t *next, 
					void *v)
{
  list_item_t *i;

  i = (list_item_t *)malloc(sizeof (*i));
  list_item_init(i, v);

  /* Assume next is actually in the list! */
  /* If it's not, we may lose the list.   */
  if (l->head == next) {
    i->next = next;
    i->pred = NULL;
    l->head = i;
    next->pred = i;
  } else {
    i->next = next;
    i->pred = next->pred;
    next->pred->next = i;
    next->pred = i;
  }
  l->length++;
}

void 
list_insert_after(	list_t *l, 
					list_item_t *pred, 
					void *v)
{
  list_item_t *i;

  i = (list_item_t *)malloc(sizeof (*i));
  list_item_init(i, v);

  /* Assume pred is actually in the list! */
  /* If it's not, we may lose the list.   */
  if (l->tail == pred) {
    i->pred = pred;
    i->next = NULL;
    l->tail = i;
    pred->next = i;
  } else {
    i->pred = pred;
    i->next = pred->next;
    pred->next->pred = i;
    pred->next = i;
  }
  l->length++;
}

void 
list_insert_sorted(	list_t *l, 
					void *v)
{
  list_item_t *itr;
  list_item_t *i;

  i = (list_item_t *)malloc(sizeof (*i));
  list_item_init(i, v);


  if (l->head) {
    for (itr = l->head; itr && l->compare(list_item_get_datum(i),
					  list_item_get_datum(itr)) < 0;
	 itr = itr->next)
      ;
    if (itr) {
      i->next = itr;
      i->pred = itr->pred;
      itr->pred = i;
      i->pred->next = i;
    } else {
      l->tail->next = i;
      i->pred = l->tail;
      i->next = NULL;
      l->tail = i;
    }
  } else {
    l->head = l->tail = i;
    i->pred = i->next = NULL;
  }
  l->length++;
}

void 
list_remove_item(	list_t *l, 
					list_item_t *i)
{
  if (i == l->head) {
    l->head = l->head->next;
    if (l->head)
      l->head->pred = NULL;
    else
      l->tail = NULL;
  } else if (i == l->tail) {
    l->tail = l->tail->pred;
    l->tail->next = NULL;
  } else {
    i->pred->next = i->next;
    i->next->pred = i->pred;
  }
  l->length--;
  list_item_delete(i, l->datum_delete);
}

void 
list_remove_head(list_t *l)
{
  list_remove_item(l, l->head);
}

void 
list_remove_tail(list_t *l)
{
  list_remove_item(l, l->tail);
}

list_item_t* 
list_find_item(	list_t *l, 
				void *datum)
{
  list_item_t *li;

  for (li = l->head; li && l->compare(datum, list_item_get_datum(li));
       li = li->next)
    ;

  return li;
}

list_item_t* 
list_get_head_item(list_t *l)
{
  return l->head;
}

list_item_t* 
list_get_tail_item(list_t *l)
{
  return l->tail;
}

void* 
list_find(	list_t *l, 
			void *datum)
{
  list_item_t *li;

  for (li = l->head; li && l->compare(datum, list_item_get_datum(li));
       li = li->next)
    ;

  return li ? li->datum : NULL;
}

void* 
list_get_head(list_t *l)
{
  return l->head ? l->head->datum : NULL;
}

void* 
list_get_tail(list_t *l)
{
  return l->tail ? l->tail->datum : NULL;
}

uint32_t 
list_get_length(list_t *l)
{
  return l->length;
}

bool 
list_is_empty(list_t *l)
{
  return (l->length == 0);
}

bool 
list_not_empty(list_t *l)
{
  return (l->length != 0);
}

void 
list_visit_items(	list_t *l, 
					void (*visitor)(void *v))
{
  list_item_t *li;

  for (li = l->head; li; li = li->next)
    visitor(list_item_get_datum(li));
}

void 
list_item_init(	list_item_t *li, 
				void *datum)
{
  li->pred = li->next = NULL;
  li->datum = datum;
}

void 
list_item_delete(	list_item_t *li, 
					void (*datum_delete)(void *datum))
{
  if (datum_delete) {
    datum_delete(li->datum);
  }

  free(li);
}

void *
list_item_get_datum(list_item_t *li)
{
  return li->datum;
}

void 
list_iterator_init(	list_t *l, 
					list_iterator_t *li)
{
  *li = l ? l->head : NULL;
}

void 
list_iterator_delete(list_iterator_t *li)
{
  *li = NULL;
}

void 
list_iterator_next(list_iterator_t *li)
{
  if (*li)
    *li = (*li)->next;
}

void 
list_iterator_prev(list_iterator_t *li)
{
  if (*li)
    *li = (*li)->pred;
}

void *
list_iterator_get_datum(list_iterator_t *li)
{
  return *li ? (*li)->datum : NULL;
}

bool 
list_iterator_is_valid(list_iterator_t *li)
{
  return (*li != NULL);
}

void 
list_reverse_iterator_init(	list_t *l, 
							list_reverse_iterator_t *li)
{
  *li = l ? l->tail : NULL;
}

void 
list_reverse_iterator_delete(list_reverse_iterator_t *li)
{
  *li = NULL;
}

void 
list_reverse_iterator_next(list_reverse_iterator_t *li)
{
  if (*li)
    *li = (*li)->pred;
}

void 
list_reverse_iterator_prev(list_reverse_iterator_t *li)
{
  if (*li)
    *li = (*li)->next;
}

void *
list_reverse_iterator_get_datum(list_reverse_iterator_t *li)
{
  return *li ? (*li)->datum : NULL;
}

bool 
list_reverse_iterator_is_valid(list_reverse_iterator_t *li)
{
  return (li != NULL);
}

//======================================================================================================================================================150
// OUTPUT AND UTILITIES
//======================================================================================================================================================150

/*   */
void *
kmalloc(int size)
{

	//printf("size: %d, current offset: %p\n",size,freeptr);
	void * r = (void *)freeptr;
	freeptr+=size;
	if(freeptr > malloc_size+(long)mem){
		printf("Memory Overflow\n");
		exit(1);
	}
	return r;
}

//transforms the current B+ Tree into a single, contiguous block of memory to be used on the GPU
long 
transform_to_cuda(	node * root, 
					bool verbose)
{

	struct timeval one,two;
	double time;
	gettimeofday (&one, NULL);
	long max_nodes = (long)(pow(order,log(size)/log(order/2.0)-1) + 1);
	malloc_size = size*sizeof(record) + max_nodes*sizeof(knode); 
	mem = (char*)malloc(malloc_size);
	if(mem==NULL){
		printf("Initial malloc error\n");
		exit(1);
	}
	freeptr = (long)mem;

	krecords = (record * )kmalloc(size*sizeof(record));
	// printf("%d records\n", size);
	knodes = (knode *)kmalloc(max_nodes*sizeof(knode));
	// printf("%d knodes\n", max_nodes);

	queue = NULL;
	enqueue(root);
	node * n;
	knode * k;
	int i;
	long nodeindex = 0;
	long recordindex = 0;
	long queueindex = 0;
	knodes[0].location = nodeindex++;
	
	while( queue != NULL ) {
		n = dequeue();
		k = &knodes[queueindex];
		k->location = queueindex++;
		k->is_leaf = n->is_leaf;
		k->num_keys = n->num_keys+2;
		//start at 1 because 0 is set to INT_MIN
		k->keys[0]=INT_MIN; 
		k->keys[k->num_keys-1]=INT_MAX;
		for(i=k->num_keys; i < order; i++)k->keys[i]=INT_MAX;
		if(!k->is_leaf){
			k->indices[0]=nodeindex++;
			// if(k->indices[0]>3953){
				// printf("ERROR: %d\n", k->indices[0]);
			// }
			for(i=1;i<k->num_keys-1;i++){
				k->keys[i] = n->keys[i-1];
				enqueue((node * )n->pointers[i-1]);
				k->indices[i] = nodeindex++;
				// if(k->indices[i]>3953){
					// printf("ERROR 1: %d\n", k->indices[i]);
				// }
				//knodes[nodeindex].location = nodeindex++;
			}
			//for final point of n
			enqueue((node * )n->pointers[i-1]);
		}
		else{
			k->indices[0]=0;
			for(i=1;i<k->num_keys-1;i++){
				k->keys[i] = n->keys[i-1];
				krecords[recordindex].value=((record *)n->pointers[i-1])->value;
				k->indices[i] = recordindex++;
				// if(k->indices[i]>3953){
					// printf("ERROR 2: %d\n", k->indices[i]);
				// }
			}
		}
		
		k->indices[k->num_keys-1]=queueindex;
		// if(k->indices[k->num_keys-1]>3953){
			// printf("ERROR 3: %d\n", k->indices[k->num_keys-1]);
		// }

		if(verbose){
			printf("Successfully created knode with index %d\n", k->location);
			printf("Is Leaf: %d, Num Keys: %d\n", k->is_leaf, k->num_keys);
			printf("Pointers: ");
			for(i=0;i<k->num_keys;i++)
				printf("%d | ", k->indices[i]);
			printf("\nKeys: ");
			for(i=0;i<k->num_keys;i++)
				printf("%d | ", k->keys[i]);
			printf("\n\n");
		}
	}
	long mem_used = size*sizeof(record)+(nodeindex)*sizeof(knode);
	if(verbose){
		for(i = 0; i < size; i++)
			printf("%d ", krecords[i].value);
		printf("\nNumber of records = %d, sizeof(record)=%d, total=%d\n",size,sizeof(record),size*sizeof(record));
		printf("Number of knodes = %d, sizeof(knode)=%d, total=%d\n",nodeindex,sizeof(knode),(nodeindex)*sizeof(knode));
		printf("\nDone Transformation. Mem used: %d\n", mem_used);
	}
	gettimeofday (&two, NULL);
	double oneD = one.tv_sec + (double)one.tv_usec * .000001;
	double twoD = two.tv_sec + (double)two.tv_usec * .000001;
	time = twoD-oneD;
	printf("Tree transformation took %f\n", time);

	return mem_used;

}

/*   */
list_t *
findRange(	node * root, 
			int start, 
			int end) 
{

	int i;
	node * c = find_leaf( root, start, false );

	if (c == NULL) return NULL;
	
	list_t * retList = (list_t *)malloc(sizeof(list_t));
	list_init(retList,NULL,NULL);
	
	int counter = 0;
	bool cont = true;
	while(cont && c!=0){
		cont = false;
		for(i = 0;i  < c->num_keys;i++){
			if(c->keys[i] >= start && c->keys[i] <= end){
				//list_insert_tail(retList,(record *)c->pointers[i]);
				counter++;
				cont = true;
			}else{
				cont = false;
				break;
			}
		}
		c = (node *)c->pointers[order-1];
	}
	return retList;
}

/* First message to the user. */
void 
usage_1( void ) 
{

	printf("B+ Tree of Order %d.\n", order);
	printf("\tAmittai Aviram -- amittai.aviram@yale.edu  Version %s\n", Version);
	printf("\tfollowing Silberschatz, Korth, Sidarshan, Database Concepts, 5th ed.\n\n");
	printf("To build a B+ tree of a different order, start again and enter the order\n");
	printf("as an integer argument:  bpt <order>.  ");
	printf("3 <= order <=20\n");
	printf("To start with input from a file of newline-delimited integers, start again and enter\n");
	printf("the order followed by the filename:  bpt <order> <inputfile>.\n");

}

/* Second message to the user. */
void 
usage_2( void ) 
{

	printf("Enter any of the following commands after the prompt > :\n");
	printf("\ti <k>  -- Insert <k> (an integer) as both key and value).\n");
	printf("\tf <k>  -- Find the value under key <k>.\n");
	printf("\tp <k> -- Print the path from the root to key k and its associated value.\n");
	printf("\td <k>  -- Delete key <k> and its associated value.\n");
	printf("\tx -- Destroy the whole tree.  Start again with an empty tree of the same order.\n");
	printf("\tt -- Print the B+ tree.\n");
	printf("\tl -- Print the keys of the leaves (bottom row of the tree).\n");
	printf("\tv -- Toggle output of pointer addresses (\"verbose\") in tree and leaves.\n");
	printf("\tq -- Quit. (Or use Ctl-D.)\n");
	printf("\t? -- Print this help message.\n");
}

/* Helper function for printing the tree out.  See print_tree. */
void 
enqueue( node* new_node ) 
{
	node * c;
	if (queue == NULL) {
		queue = new_node;
		queue->next = NULL;
	}
	else {
		c = queue;
		while(c->next != NULL) {
			c = c->next;
		}
		c->next = new_node;
		new_node->next = NULL;
	}
}

/* Helper function for printing the tree out.  See print_tree. */
node *
dequeue( void ) 
{
	node * n = queue;
	queue = queue->next;
	n->next = NULL;
	return n;
}

/* Prints the bottom row of keys of the tree (with their respective pointers, if the verbose_output flag is set. */
void 
print_leaves( node* root ) 
{
	int i;
	node * c = root;
	if (root == NULL) {
		printf("Empty tree.\n");
		return;
	}
	while (!c->is_leaf)
	c = (node *) c->pointers[0];
	while (true) {
		for (i = 0; i < c->num_keys; i++) {
			if (verbose_output)
			//printf("%x ", (unsigned int)c->pointers[i]);
			printf("%d ", c->keys[i]);
		}
		if (verbose_output)
		//printf("%x ", (unsigned int)c->pointers[order - 1]);
		if (c->pointers[order - 1] != NULL) {
			printf(" | ");
			c = (node *) c->pointers[order - 1];
		}
		else
		break;
	}
	printf("\n");
}

/* Utility function to give the height of the tree, which length in number of edges of the path from the root to any leaf. */
int 
height( node* root ) 
{
	int h = 0;
	node * c = root;
	while (!c->is_leaf) {
		c = (node *) c->pointers[0];
		h++;
	}
	return h;
}

/* Utility function to give the length in edges of the path from any node to the root. */
int 
path_to_root( node* root, node* child ) 
{
	int length = 0;
	node * c = child;
	while (c != root) {
		c = c->parent;
		length++;
	}
	return length;
}

/* Prints the B+ tree in the command line in level (rank) order, with the keys in each node and the '|' symbol to separate nodes. With the verbose_output flag set. the values of the pointers corresponding to the keys also appear next to their respective keys, in hexadecimal notation. */
void 
print_tree( node* root ) 
{

	node * n = NULL;
	int i = 0;
	int rank = 0;
	int new_rank = 0;

	if (root == NULL) {
		printf("Empty tree.\n");
		return;
	}
	queue = NULL;
	enqueue(root);
	while( queue != NULL ) {
		n = dequeue();
		if (n->parent != NULL && n == n->parent->pointers[0]) {
			new_rank = path_to_root( root, n );
			if (new_rank != rank) {
				rank = new_rank;
				printf("\n");
			}
		}
		if (verbose_output) 
		printf("(%x)", n);
		for (i = 0; i < n->num_keys; i++) {
			if (verbose_output)
			printf("%x ", n->pointers[i]);
			printf("%d ", n->keys[i]);
		}
		if (!n->is_leaf)
		for (i = 0; i <= n->num_keys; i++)
		enqueue((node *) n->pointers[i]);
		if (verbose_output) {
			if (n->is_leaf) 
			printf("%x ", n->pointers[order - 1]);
			else
			printf("%x ", n->pointers[n->num_keys]);
		}
		printf("| ");
	}
	printf("\n");
}

/* Traces the path from the root to a leaf, searching by key.  Displays information about the path if the verbose flag is set. Returns the leaf containing the given key. */
node *
find_leaf( node* root, int key, bool verbose ) 
{

	int i = 0;
	node * c = root;
	if (c == NULL) {
		if (verbose) 
			printf("Empty tree.\n");
		return c;
	}
	while (!c->is_leaf) {
		if (verbose) {
			printf("[");
			for (i = 0; i < c->num_keys - 1; i++)
				printf("%d ", c->keys[i]);
			printf("%d] ", c->keys[i]);
		}
		i = 0;
		while (i < c->num_keys) {
			if (key >= c->keys[i]) 
				i++;
			else 
				break;
		}
		if (verbose)
			printf("%d ->\n", i);
		c = (node *)c->pointers[i];
	}
	if (verbose) {
		printf("Leaf [");
		for (i = 0; i < c->num_keys - 1; i++)
			printf("%d ", c->keys[i]);
		printf("%d] ->\n", c->keys[i]);
	}
	return c;

}

/* Finds and returns the record to which a key refers. */
record *
find( node* root, int key, bool verbose ) 
{

	int i = 0;
	node * c = find_leaf( root, key, verbose );
	if (c == NULL) 
		return NULL;
	for (i = 0; i < c->num_keys; i++)
		if (c->keys[i] == key) 
			break;
	if (i == c->num_keys) 
		return NULL;
	else
		return (record *)c->pointers[i];

}

/* Finds the appropriate place to split a node that is too big into two. */
int 
cut( int length ) 
{
	if (length % 2 == 0)
	return length/2;
	else
	return length/2 + 1;
}

//======================================================================================================================================================150
// INSERTION
//======================================================================================================================================================150

/* Creates a new record to hold the value to which a key refers. */
record *
make_record(int value) 
{
	record * new_record = (record *)malloc(sizeof(record));
	if (new_record == NULL) {
		perror("Record creation.");
		exit(EXIT_FAILURE);
	}
	else {
		new_record->value = value;
	}
	return new_record;
}

/* Creates a new general node, which can be adapted to serve as either a leaf or an internal node. */
node *
make_node( void ) 
{
	node * new_node;
	new_node = (node *) malloc(sizeof(node));
	if (new_node == NULL) {
		perror("Node creation.");
		exit(EXIT_FAILURE);
	}
	new_node->keys = (int *) malloc( (order - 1) * sizeof(int) );
	if (new_node->keys == NULL) {
		perror("New node keys array.");
		exit(EXIT_FAILURE);
	}
	new_node->pointers = (void **) malloc( order * sizeof(void *) );
	if (new_node->pointers == NULL) {
		perror("New node pointers array.");
		exit(EXIT_FAILURE);
	}
	new_node->is_leaf = false;
	new_node->num_keys = 0;
	new_node->parent = NULL;
	new_node->next = NULL;
	return new_node;
}

/* Creates a new leaf by creating a node and then adapting it appropriately. */
node *
make_leaf( void ) 
{
	node* leaf = make_node();
	leaf->is_leaf = true;
	return leaf;
}

/* Helper function used in insert_into_parent to find the index of the parent's pointer to the node to the left of the key to be inserted. */
int 
get_left_index(node* parent, node* left) 
{

	int left_index = 0;
	while (left_index <= parent->num_keys && 
	parent->pointers[left_index] != left)
	left_index++;
	return left_index;
}

/* Inserts a new pointer to a record and its corresponding key into a leaf. Returns the altered leaf. */
node *
insert_into_leaf( node* leaf, int key, record* pointer ) 
{

	int i, insertion_point;

	insertion_point = 0;
	while (insertion_point < leaf->num_keys && leaf->keys[insertion_point] < key)
	insertion_point++;

	for (i = leaf->num_keys; i > insertion_point; i--) {
		leaf->keys[i] = leaf->keys[i - 1];
		leaf->pointers[i] = leaf->pointers[i - 1];
	}
	leaf->keys[insertion_point] = key;
	leaf->pointers[insertion_point] = pointer;
	leaf->num_keys++;
	return leaf;
}

/* Inserts a new key and pointer to a new record into a leaf so as to exceed the tree's order, causing the leaf to be split in half. */
node *
insert_into_leaf_after_splitting(	node* root, 
									node* leaf, 
									int key, 
									record* pointer) 
{

	node * new_leaf;
	int * temp_keys;
	void ** temp_pointers;
	int insertion_index, split, new_key, i, j;

	new_leaf = make_leaf();

	temp_keys = (int *) malloc( order * sizeof(int) );
	if (temp_keys == NULL) {
		perror("Temporary keys array.");
		exit(EXIT_FAILURE);
	}

	temp_pointers = (void **) malloc( order * sizeof(void *) );
	if (temp_pointers == NULL) {
		perror("Temporary pointers array.");
		exit(EXIT_FAILURE);
	}

	insertion_index = 0;
	while (leaf->keys[insertion_index] < key && insertion_index < order - 1)
	insertion_index++;

	for (i = 0, j = 0; i < leaf->num_keys; i++, j++) {
		if (j == insertion_index) j++;
		temp_keys[j] = leaf->keys[i];
		temp_pointers[j] = leaf->pointers[i];
	}

	temp_keys[insertion_index] = key;
	temp_pointers[insertion_index] = pointer;

	leaf->num_keys = 0;

	split = cut(order - 1);

	for (i = 0; i < split; i++) {
		leaf->pointers[i] = temp_pointers[i];
		leaf->keys[i] = temp_keys[i];
		leaf->num_keys++;
	}

	for (i = split, j = 0; i < order; i++, j++) {
		new_leaf->pointers[j] = temp_pointers[i];
		new_leaf->keys[j] = temp_keys[i];
		new_leaf->num_keys++;
	}

	free(temp_pointers);
	free(temp_keys);

	new_leaf->pointers[order - 1] = leaf->pointers[order - 1];
	leaf->pointers[order - 1] = new_leaf;

	for (i = leaf->num_keys; i < order - 1; i++)
	leaf->pointers[i] = NULL;
	for (i = new_leaf->num_keys; i < order - 1; i++)
	new_leaf->pointers[i] = NULL;

	new_leaf->parent = leaf->parent;
	new_key = new_leaf->keys[0];

	return insert_into_parent(root, leaf, new_key, new_leaf);
}

/* Inserts a new key and pointer to a node into a node into which these can fit without violating the B+ tree properties. */
node *
insert_into_node(	node* root, 
					node* n, 
					int left_index, 
					int key, 
					node* right) 
{

	int i;

	for (i = n->num_keys; i > left_index; i--) {
		n->pointers[i + 1] = n->pointers[i];
		n->keys[i] = n->keys[i - 1];
	}
	n->pointers[left_index + 1] = right;
	n->keys[left_index] = key;
	n->num_keys++;
	return root;
}

/* Inserts a new key and pointer to a node into a node, causing the node's size to exceed the order, and causing the node to split into two. */
node *
insert_into_node_after_splitting(	node* root, 
									node* old_node, 
									int left_index, 
									int key, 
									node * right) 
{

	int i, j, split, k_prime;
	node * new_node, * child;
	int * temp_keys;
	node ** temp_pointers;

	/* First create a temporary set of keys and pointers
* to hold everything in order, including
* the new key and pointer, inserted in their
* correct places. 
* Then create a new node and copy half of the 
* keys and pointers to the old node and
* the other half to the new.
*/

	temp_pointers = (node **) malloc( (order + 1) * sizeof(node *) );
	if (temp_pointers == NULL) {
		perror("Temporary pointers array for splitting nodes.");
		exit(EXIT_FAILURE);
	}
	temp_keys = (int *) malloc( order * sizeof(int) );
	if (temp_keys == NULL) {
		perror("Temporary keys array for splitting nodes.");
		exit(EXIT_FAILURE);
	}

	for (i = 0, j = 0; i < old_node->num_keys + 1; i++, j++) {
		if (j == left_index + 1) j++;
		temp_pointers[j] = (node *) old_node->pointers[i];
	}

	for (i = 0, j = 0; i < old_node->num_keys; i++, j++) {
		if (j == left_index) j++;
		temp_keys[j] = old_node->keys[i];
	}

	temp_pointers[left_index + 1] = right;
	temp_keys[left_index] = key;

	/* Create the new node and copy
* half the keys and pointers to the
* old and half to the new.
*/  
	split = cut(order);
	new_node = make_node();
	old_node->num_keys = 0;
	for (i = 0; i < split - 1; i++) {
		old_node->pointers[i] = temp_pointers[i];
		old_node->keys[i] = temp_keys[i];
		old_node->num_keys++;
	}
	old_node->pointers[i] = temp_pointers[i];
	k_prime = temp_keys[split - 1];
	for (++i, j = 0; i < order; i++, j++) {
		new_node->pointers[j] = temp_pointers[i];
		new_node->keys[j] = temp_keys[i];
		new_node->num_keys++;
	}
	new_node->pointers[j] = temp_pointers[i];
	free(temp_pointers);
	free(temp_keys);
	new_node->parent = old_node->parent;
	for (i = 0; i <= new_node->num_keys; i++) {
		child = (node *) new_node->pointers[i];
		child->parent = new_node;
	}

	/* Insert a new key into the parent of the two
* nodes resulting from the split, with
* the old node to the left and the new to the right.
*/

	return insert_into_parent(root, old_node, k_prime, new_node);
}

/* Inserts a new node (leaf or internal node) into the B+ tree. Returns the root of the tree after insertion. */
node *
insert_into_parent(	node* root, 
					node* left, 
					int key, 
					node* right) 
{

	int left_index;
	node * parent;

	parent = left->parent;

	/* Case: new root. */

	if (parent == NULL)
	return insert_into_new_root(left, key, right);

	/* Case: leaf or node. (Remainder of
* function body.)  
*/

	/* Find the parent's pointer to the left 
* node.
*/

	left_index = get_left_index(parent, left);


	/* Simple case: the new key fits into the node. 
*/

	if (parent->num_keys < order - 1)
	return insert_into_node(root, parent, left_index, key, right);

	/* Harder case:  split a node in order 
* to preserve the B+ tree properties.
*/

	return insert_into_node_after_splitting(root, parent, left_index, key, right);
}

/* Creates a new root for two subtrees and inserts the appropriate key into the new root. */
node *
insert_into_new_root(	node* left, 
						int key, 
						node* right) 
{

	node * root = make_node();
	root->keys[0] = key;
	root->pointers[0] = left;
	root->pointers[1] = right;
	root->num_keys++;
	root->parent = NULL;
	left->parent = root;
	right->parent = root;
	return root;
}

/* First insertion: start a new tree. */
node *
start_new_tree(	int key, 
				record* pointer) 
{

	node * root = make_leaf();
	root->keys[0] = key;
	root->pointers[0] = pointer;
	root->pointers[order - 1] = NULL;
	root->parent = NULL;
	root->num_keys++;
	return root;
}

/* Master insertion function. Inserts a key and an associated value into the B+ tree, causing the tree to be adjusted however necessary to maintain the B+ tree properties. */
node *
insert(	node* root, 
		int key, 
		int value ) 
{

	record* pointer;
	node* leaf;

	/* The current implementation ignores duplicates. */
	if (find(root, key, false) != NULL)
		return root;

	/* Create a new record for the value. */
	pointer = make_record(value);

	/* Case: the tree does not exist yet. Start a new tree. */
	if (root == NULL) 
		return start_new_tree(key, pointer);

	/* Case: the tree already exists. (Rest of function body.) */
	leaf = find_leaf(root, key, false);

	/* Case: leaf has room for key and pointer. */
	if (leaf->num_keys < order - 1) {
		leaf = insert_into_leaf(leaf, key, pointer);
		return root;
	}

	/* Case:  leaf must be split. */
	return insert_into_leaf_after_splitting(root, leaf, key, pointer);
}

//======================================================================================================================================================150
// DELETION
//======================================================================================================================================================150

/* Utility function for deletion. Retrieves the index of a node's nearest neighbor (sibling) to the left if one exists.  If not (the node is the leftmost child), returns -1 to signify this special case. */
int 
get_neighbor_index( node* n ) 
{

	int i;

	/* Return the index of the key to the left
* of the pointer in the parent pointing
* to n.  
* If n is the leftmost child, this means
* return -1.
*/
	for (i = 0; i <= n->parent->num_keys; i++)
	if (n->parent->pointers[i] == n)
	return i - 1;

	// Error state.
	printf("Search for nonexistent pointer to node in parent.\n");
	//printf("Node:  %#x\n", (unsigned int)n);
	exit(EXIT_FAILURE);
}

/*   */
node* 
remove_entry_from_node(	node* n, 
						int key, 
						node * pointer) 
{

	int i, num_pointers;

	// Remove the key and shift other keys accordingly.
	i = 0;
	while (n->keys[i] != key)
	i++;
	for (++i; i < n->num_keys; i++)
	n->keys[i - 1] = n->keys[i];

	// Remove the pointer and shift other pointers accordingly.
	// First determine number of pointers.
	num_pointers = n->is_leaf ? n->num_keys : n->num_keys + 1;
	i = 0;
	while (n->pointers[i] != pointer)
	i++;
	for (++i; i < num_pointers; i++)
	n->pointers[i - 1] = n->pointers[i];


	// One key fewer.
	n->num_keys--;

	// Set the other pointers to NULL for tidiness.
	// A leaf uses the last pointer to point to the next leaf.
	if (n->is_leaf)
	for (i = n->num_keys; i < order - 1; i++)
	n->pointers[i] = NULL;
	else
	for (i = n->num_keys + 1; i < order; i++)
	n->pointers[i] = NULL;

	return n;
}

/*   */
node* 
adjust_root(node* root) 
{

	node * new_root;

	/* Case: nonempty root.
* Key and pointer have already been deleted,
* so nothing to be done.
*/

	if (root->num_keys > 0)
	return root;

	/* Case: empty root. 
*/

	// If it has a child, promote 
	// the first (only) child
	// as the new root.

	if (!root->is_leaf) {
		new_root = (node *) root->pointers[0];
		new_root->parent = NULL;
	}

	// If it is a leaf (has no children),
	// then the whole tree is empty.

	else
	new_root = NULL;

	free(root->keys);
	free(root->pointers);
	free(root);

	return new_root;
}

/* Coalesces a node that has become too small after deletion with a neighboring node that can accept the additional entries without exceeding the maximum. */
node* 
coalesce_nodes(	node* root, 
				node* n, 
				node* neighbor, 
				int neighbor_index, 
				int k_prime) 
				{

	int i, j, neighbor_insertion_index, n_start, n_end, new_k_prime;
	node * tmp;
	bool split;

	/* Swap neighbor with node if node is on the
* extreme left and neighbor is to its right.
*/

	if (neighbor_index == -1) {
		tmp = n;
		n = neighbor;
		neighbor = tmp;
	}

	/* Starting point in the neighbor for copying
* keys and pointers from n.
* Recall that n and neighbor have swapped places
* in the special case of n being a leftmost child.
*/

	neighbor_insertion_index = neighbor->num_keys;
	
	/*
* Nonleaf nodes may sometimes need to remain split,
* if the insertion of k_prime would cause the resulting
* single coalesced node to exceed the limit order - 1.
* The variable split is always false for leaf nodes
* and only sometimes set to true for nonleaf nodes.
*/

	split = false;

	/* Case:  nonleaf node.
* Append k_prime and the following pointer.
* If there is room in the neighbor, append
* all pointers and keys from the neighbor.
* Otherwise, append only cut(order) - 2 keys and
* cut(order) - 1 pointers.
*/

	if (!n->is_leaf) {

		/* Append k_prime.
	*/

		neighbor->keys[neighbor_insertion_index] = k_prime;
		neighbor->num_keys++;


		/* Case (default):  there is room for all of n's keys and pointers
	* in the neighbor after appending k_prime.
	*/

		n_end = n->num_keys;

		/* Case (special): k cannot fit with all the other keys and pointers
	* into one coalesced node.
	*/
		n_start = 0; // Only used in this special case.
		if (n->num_keys + neighbor->num_keys >= order) {
			split = true;
			n_end = cut(order) - 2;
		}

		for (i = neighbor_insertion_index + 1, j = 0; j < n_end; i++, j++) {
			neighbor->keys[i] = n->keys[j];
			neighbor->pointers[i] = n->pointers[j];
			neighbor->num_keys++;
			n->num_keys--;
			n_start++;
		}

		/* The number of pointers is always
	* one more than the number of keys.
	*/

		neighbor->pointers[i] = n->pointers[j];

		/* If the nodes are still split, remove the first key from
	* n.
	*/
		if (split) {
			new_k_prime = n->keys[n_start];
			for (i = 0, j = n_start + 1; i < n->num_keys; i++, j++) {
				n->keys[i] = n->keys[j];
				n->pointers[i] = n->pointers[j];
			}
			n->pointers[i] = n->pointers[j];
			n->num_keys--;
		}

		/* All children must now point up to the same parent.
	*/

		for (i = 0; i < neighbor->num_keys + 1; i++) {
			tmp = (node *)neighbor->pointers[i];
			tmp->parent = neighbor;
		}
	}

	/* In a leaf, append the keys and pointers of
* n to the neighbor.
* Set the neighbor's last pointer to point to
* what had been n's right neighbor.
*/

	else {
		for (i = neighbor_insertion_index, j = 0; j < n->num_keys; i++, j++) {
			neighbor->keys[i] = n->keys[j];
			neighbor->pointers[i] = n->pointers[j];
			neighbor->num_keys++;
		}
		neighbor->pointers[order - 1] = n->pointers[order - 1];
	}

	if (!split) {
		root = delete_entry(root, n->parent, k_prime, n);
		free(n->keys);
		free(n->pointers);
		free(n); 
	}
	else
	for (i = 0; i < n->parent->num_keys; i++)
	if (n->parent->pointers[i + 1] == n) {
		n->parent->keys[i] = new_k_prime;
		break;
	}

	return root;

}

/* Redistributes entries between two nodes when one has become too small after deletion but its neighbor is too big to append the small node's entries without exceeding the maximum */
node* 
redistribute_nodes(	node* root, 
					node* n, 
					node* neighbor, 
					int neighbor_index, 
					int k_prime_index, 
					int k_prime) 
{  

	int i;
	node * tmp;

	/* Case: n has a neighbor to the left. 
* Pull the neighbor's last key-pointer pair over
* from the neighbor's right end to n's left end.
*/

	if (neighbor_index != -1) {
		if (!n->is_leaf)
		n->pointers[n->num_keys + 1] = n->pointers[n->num_keys];
		for (i = n->num_keys; i > 0; i--) {
			n->keys[i] = n->keys[i - 1];
			n->pointers[i] = n->pointers[i - 1];
		}
		if (!n->is_leaf) {
			n->pointers[0] = neighbor->pointers[neighbor->num_keys];
			tmp = (node *)n->pointers[0];
			tmp->parent = n;
			neighbor->pointers[neighbor->num_keys] = NULL;
			n->keys[0] = k_prime;
			n->parent->keys[k_prime_index] = neighbor->keys[neighbor->num_keys - 1];
		}
		else {
			n->pointers[0] = neighbor->pointers[neighbor->num_keys - 1];
			neighbor->pointers[neighbor->num_keys - 1] = NULL;
			n->keys[0] = neighbor->keys[neighbor->num_keys - 1];
			n->parent->keys[k_prime_index] = n->keys[0];
		}
	}

	/* Case: n is the leftmost child.
* Take a key-pointer pair from the neighbor to the right.
* Move the neighbor's leftmost key-pointer pair
* to n's rightmost position.
*/

	else {  
		if (n->is_leaf) {
			n->keys[n->num_keys] = neighbor->keys[0];
			n->pointers[n->num_keys] = neighbor->pointers[0];
			n->parent->keys[k_prime_index] = neighbor->keys[1];
		}
		else {
			n->keys[n->num_keys] = k_prime;
			n->pointers[n->num_keys + 1] = neighbor->pointers[0];
			tmp = (node *)n->pointers[n->num_keys + 1];
			tmp->parent = n;
			n->parent->keys[k_prime_index] = neighbor->keys[0];
		}
		for (i = 0; i < neighbor->num_keys; i++) {
			neighbor->keys[i] = neighbor->keys[i + 1];
			neighbor->pointers[i] = neighbor->pointers[i + 1];
		}
		if (!n->is_leaf)
		neighbor->pointers[i] = neighbor->pointers[i + 1];
	}

	/* n now has one more key and one more pointer;
* the neighbor has one fewer of each.
*/

	n->num_keys++;
	neighbor->num_keys--;

	return root;
}

/* Deletes an entry from the B+ tree. Removes the record and its key and pointer from the leaf, and then makes all appropriate changes to preserve the B+ tree properties. */
node* 
delete_entry(	node* root, 
				node* n, 
				int key, 
				void* pointer ) 
{

	int min_keys;
	node * neighbor;
	int neighbor_index;
	int k_prime_index, k_prime;
	int capacity;

	// Remove key and pointer from node.

	n = remove_entry_from_node(n, key, (node *) pointer);

	/* Case:  deletion from the root. 
*/

	if (n == root) 
	return adjust_root(root);


	/* Case:  deletion from a node below the root.
* (Rest of function body.)
*/

	/* Determine minimum allowable size of node,
* to be preserved after deletion.
*/

	min_keys = n->is_leaf ? cut(order - 1) : cut(order) - 1;

	/* Case:  node stays at or above minimum.
* (The simple case.)
*/

	if (n->num_keys >= min_keys)
	return root;

	/* Case:  node falls below minimum.
* Either coalescence or redistribution
* is needed.
*/

	/* Find the appropriate neighbor node with which
* to coalesce.
* Also find the key (k_prime) in the parent
* between the pointer to node n and the pointer
* to the neighbor.
*/

	neighbor_index = get_neighbor_index( n );
	k_prime_index = neighbor_index == -1 ? 0 : neighbor_index;
	k_prime = n->parent->keys[k_prime_index];
	neighbor = neighbor_index == -1 ? (node *) n->parent->pointers[1] : 
	(node *)n->parent->pointers[neighbor_index];

	capacity = n->is_leaf ? order : order - 1;

	/* Coalescence. */

	if (neighbor->num_keys + n->num_keys < capacity)
	return coalesce_nodes(root, n, neighbor, neighbor_index, k_prime);

	/* Redistribution. */

	else
	return redistribute_nodes(root, n, neighbor, neighbor_index, k_prime_index, k_prime);
}

/* Master deletion function. */
node* 
deleteVal(	node* root, 
			int key) 
{

	node * key_leaf;
	record * key_record;

	key_record = find(root, key, false);
	key_leaf = find_leaf(root, key, false);
	if (key_record != NULL && key_leaf != NULL) {
		free(key_record);
		root = delete_entry(root, key_leaf, key, key_record);
	}
	return root;
}

/*   */
void 
destroy_tree_nodes(node* root) 
{
	int i;
	if (root->is_leaf)
	for (i = 0; i < root->num_keys; i++)
	free(root->pointers[i]);
	else
	for (i = 0; i < root->num_keys + 1; i++)
	destroy_tree_nodes((node *) root->pointers[i]);
	free(root->pointers);
	free(root->keys);
	free(root);
}

/*   */
node* 
destroy_tree(node* root) 
{
	destroy_tree_nodes(root);
	return NULL;
}

//======================================================================================================================================================150
//	END
//======================================================================================================================================================150

//========================================================================================================================================================================================================200
//	MAIN FUNCTION
//========================================================================================================================================================================================================200

int 
main(	int argc, 
		char** argv ) 
{

  printf("WG size of kernel 1 = %d WG size of kernel 2 = %d \n", DEFAULT_ORDER, DEFAULT_ORDER_2);
	// ------------------------------------------------------------60
	// figure out and display whether 32-bit or 64-bit architecture
	// ------------------------------------------------------------60

	// if(sizeof(int *)==8){
		// printf("64 bit machine\n");
	// }
	// else if(sizeof(int *)==4){
		// printf("32 bit machine\n");
	// }

	// ------------------------------------------------------------60
	// read inputs
	// ------------------------------------------------------------60

	// assing default values
	int cur_arg;
	int arch_arg;
	arch_arg = 0;
	int cores_arg;
	cores_arg = 1;
	char *input_file = NULL;
	char *command_file = NULL;
	char *output="output.txt";
	FILE * pFile;

	// go through arguments
	for(cur_arg=1; cur_arg<argc; cur_arg++){
	  // check if -file
	  if(strcmp(argv[cur_arg], "file")==0){
	    // check if value provided
	    if(argc>=cur_arg+1){
	      input_file = argv[cur_arg+1];
	      cur_arg = cur_arg+1;
	      // value is not a number
	    }
	    // value not provided
	    else{
	      printf("ERROR: Missing value to -file parameter\n");
	      return -1;
	    }
	  }
	  else if(strcmp(argv[cur_arg], "command")==0){
	    // check if value provided
	    if(argc>=cur_arg+1){
	      command_file = argv[cur_arg+1];
	      cur_arg = cur_arg+1;
	      // value is not a number
	    }
	    // value not provided
	    else{
	      printf("ERROR: Missing value to command parameter\n");
	      return -1;
	    }
	  }
	}
	// Print configuration
	  if((input_file==NULL)||(command_file==NULL))
	    printf("Usage: ./b+tree file input_file command command_list\n");

	  // For debug
	  printf("Input File: %s \n", input_file);
	  printf("Command File: %s \n", command_file);


     FILE * commandFile;
     long lSize;
     char * commandBuffer;
     size_t result;

     commandFile = fopen ( command_file, "rb" );
     if (commandFile==NULL) {fputs ("Command File error",stderr); exit (1);}
     
     // obtain file size:
     fseek (commandFile , 0 , SEEK_END);
     lSize = ftell (commandFile);
     rewind (commandFile);

     // allocate memory to contain the whole file:
     commandBuffer = (char*) malloc (sizeof(char)*lSize);
     if (commandBuffer == NULL) {fputs ("Command Buffer memory error",stderr); exit (2);}
     
     // copy the file into the buffer:
     result = fread (commandBuffer,1,lSize,commandFile);
     if (result != lSize) {fputs ("Command file reading error",stderr); exit (3);}

     /* the whole file is now loaded in the memory buffer. */

  // terminate
     fclose (commandFile);

     // For Debug
     char *sPointer=commandBuffer;
     printf("Command Buffer: \n");
     printf("%s",commandBuffer);
     //


     pFile = fopen (output,"w+");
     if (pFile==NULL) 
       fputs ("Fail to open %s !\n",output);
     fprintf(pFile,"******starting******\n");
     fclose(pFile);

	// ------------------------------------------------------------60
	// general variables
	// ------------------------------------------------------------60

	FILE *file_pointer;
	node *root;
	root = NULL;
	record *r;
	int input;
	char instruction;
	order = DEFAULT_ORDER_2;
	verbose_output = false;

	//usage_1();  
	//usage_2();

	// ------------------------------------------------------------60
	// get input from file, if file provided
	// ------------------------------------------------------------60

	if (input_file != NULL) {

		printf("Getting input from file %s...\n", argv[1]);

		// open input file
		file_pointer = fopen(input_file, "r");
		if (file_pointer == NULL) {
			perror("Failure to open input file.");
			exit(EXIT_FAILURE);
		}

		// get # of numbers in the file
		fscanf(file_pointer, "%d\n", &input);
		size = input;

		// save all numbers
		while (!feof(file_pointer)) {
			fscanf(file_pointer, "%d\n", &input);
			root = insert(root, input, input);
		}

		// close file
		fclose(file_pointer);
		//print_tree(root);
		//printf("Height of tree = %d\n", height(root));

	}
	else{
		printf("ERROR: Argument -file missing\n");
		return 0;
	}

	// ------------------------------------------------------------60
	// get tree statistics
	// ------------------------------------------------------------60

	printf("Transforming data to a GPU suitable structure...\n");
	long mem_used = transform_to_cuda(root,0);
	maxheight = height(root);
	long rootLoc = (long)knodes - (long)mem;

	// ------------------------------------------------------------60
	// process commands
	// ------------------------------------------------------------60
	char *commandPointer=commandBuffer;
	printf("Waiting for command\n");
	printf("> ");
	while (sscanf(commandPointer, "%c", &instruction) != EOF) {
	  commandPointer++;
	  switch (instruction) {
			// ----------------------------------------40
			// Insert
			// ----------------------------------------40

			case 'i':
			{
				scanf("%d", &input);
				while (getchar() != (int)'\n');
				root = insert(root, input, input);
				print_tree(root);
				break;
			}

			// ----------------------------------------40
			// n/a
			// ----------------------------------------40

			case 'f':
			{
			}

			// ----------------------------------------40
			// find
			// ----------------------------------------40

			case 'p':
			{
				scanf("%d", &input);
				while (getchar() != (int)'\n');
				r = find(root, input, instruction == 'p');
				if (r == NULL)
				printf("Record not found under key %d.\n", input);
				else 
				printf("Record found: %d\n",r->value);
				break;
			}

			// ----------------------------------------40
			// delete value
			// ----------------------------------------40

			case 'd':
			{
				scanf("%d", &input);
				while (getchar() != (int)'\n');
				root = (node *) deleteVal(root, input);
				print_tree(root);
				break;
			}

			// ----------------------------------------40
			// destroy tree
			// ----------------------------------------40

			case 'x':
			{
				while (getchar() != (int)'\n');
				root = destroy_tree(root);
				print_tree(root);
				break;
			}

			// ----------------------------------------40
			// print leaves
			// ----------------------------------------40

			case 'l':
			{
				while (getchar() != (int)'\n');
				print_leaves(root);
				break;
			}

			// ----------------------------------------40
			// print tree
			// ----------------------------------------40

			case 't':
			{
				while (getchar() != (int)'\n');
				print_tree(root);
				break;
			}

			// ----------------------------------------40
			// toggle verbose output
			// ----------------------------------------40

			case 'v':
			{
				while (getchar() != (int)'\n');
				verbose_output = !verbose_output;
				break;
			}

			// ----------------------------------------40
			// quit
			// ----------------------------------------40

			case 'q':
			{
				while (getchar() != (int)'\n');
				return EXIT_SUCCESS;
			}

			// ----------------------------------------40
			// [GPU] find K (initK, findK)
			// ----------------------------------------40

			case 'k':
			{

				// get # of queries from user
				int count;
				sscanf(commandPointer, "%d", &count);
				while(*commandPointer!=32 && commandPointer!='\n')
				  commandPointer++;

				printf("\n ******command: k count=%d \n",count);
				if(count > 65535){
					printf("ERROR: Number of requested querries should be 65,535 at most. (limited by # of CUDA blocks)\n");
					exit(0);
				}

				// INPUT: records CPU allocation (setting pointer in mem variable)
				record *records = (record *)mem;
				long records_elem = (long)rootLoc / sizeof(record);
				long records_mem = (long)rootLoc;
				printf("records_elem=%d, records_unit_mem=%d, records_mem=%d\n", (int)records_elem, (int)sizeof(record), (int)records_mem);

				// INPUT: knodes CPU allocation (setting pointer in mem variable)
				knode *knodes = (knode *)((long)mem + (long)rootLoc);
				long knodes_elem = ((long)(mem_used) - (long)rootLoc) / sizeof(knode);
				long knodes_mem = (long)(mem_used) - (long)rootLoc;
				printf("knodes_elem=%d, knodes_unit_mem=%d, knodes_mem=%d\n", (int)knodes_elem, (int)sizeof(knode), (int)knodes_mem);

				// INPUT: currKnode CPU allocation
				long *currKnode;
				currKnode = (long *)malloc(count*sizeof(long));
				// INPUT: offset CPU initialization
				memset(currKnode, 0, count*sizeof(long));

				// INPUT: offset CPU allocation
				long *offset;
				offset = (long *)malloc(count*sizeof(long));
				// INPUT: offset CPU initialization
				memset(offset, 0, count*sizeof(long));

				// INPUT: keys CPU allocation
				int *keys;
				keys = (int *)malloc(count*sizeof(int));
				// INPUT: keys CPU initialization
				int i;
				for(i = 0; i < count; i++){
					keys[i] = (rand()/(float)RAND_MAX)*size;
				}

				// OUTPUT: ans CPU allocation
				record *ans = (record *)malloc(sizeof(record)*count);
				// OUTPUT: ans CPU initialization
				for(i = 0; i < count; i++){
					ans[i].value = -1;
				}

				// OpenCL kernel
				kernel_gpu_opencl_wrapper(	records,
											records_mem,
											knodes,
											knodes_elem,
											knodes_mem,

											order,
											maxheight,
											count,

											currKnode,
											offset,
											keys,
											ans);

				pFile = fopen (output,"aw+");
				if (pFile==NULL)
				  {
				    fputs ("Fail to open %s !\n",output);
				  }
				
				fprintf(pFile,"\n ******command: k count=%d \n",count);
				for(i = 0; i < count; i++){
				  fprintf(pFile, "%d    %d\n",i, ans[i].value);
				}
				fprintf(pFile, " \n");
                                fclose(pFile);
				

				// free memory
				free(currKnode);
				free(offset);
				free(keys);
				free(ans);

				// break out of case
				break;

			}

			// ----------------------------------------40
			// find range
			// ----------------------------------------40

			case 'r':
			{
				int start, end;
				scanf("%d", &start);
				scanf("%d", &end);
				if(start > end){
					input = start;
					start = end;
					end = input;
				}
				printf("For range %d to %d, ",start,end);
				list_t * ansList;
				ansList = findRange(root, start, end);
				printf("%d records found\n", list_get_length(ansList));
				//list_iterator_t iter;
				free(ansList);
				break;
			}

			// ----------------------------------------40
			// [GPU] find Range K (initK, findRangeK)
			// ----------------------------------------40

			case 'j':
			{

				// get # of queries from user
				int count;
				sscanf(commandPointer, "%d", &count);
				while(*commandPointer!=32 && commandPointer!='\n')
				  commandPointer++;

				int rSize;
				sscanf(commandPointer, "%d", &rSize);
				while(*commandPointer!=32 && commandPointer!='\n')
				  commandPointer++;

				printf("\n******command: j count=%d, rSize=%d \n",count, rSize);

				if(rSize > size || rSize < 0) {
					printf("Search range size is larger than data set size %d.\n", (int)size);
					exit(0);
				}

				// INPUT: knodes CPU allocation (setting pointer in mem variable)
				knode *knodes = (knode *)((long)mem + (long)rootLoc);
				long knodes_elem = ((long)(mem_used) - (long)rootLoc) / sizeof(knode);
				long knodes_mem = (long)(mem_used) - (long)rootLoc;
				printf("knodes_elem=%d, knodes_unit_mem=%d, knodes_mem=%d\n", (int)knodes_elem, (int)sizeof(knode), (int)knodes_mem);

				// INPUT: currKnode CPU allocation
				long *currKnode;
				currKnode = (long *)malloc(count*sizeof(long));
				// INPUT: offset CPU initialization
				memset (currKnode, 0, count*sizeof(long));

				// INPUT: offset CPU allocation
				long *offset;
				offset = (long *)malloc(count*sizeof(long));
				// INPUT: offset CPU initialization
				memset (offset, 0, count*sizeof(long));

				// INPUT: lastKnode CPU allocation
				long *lastKnode;
				lastKnode = (long *)malloc(count*sizeof(long));
				// INPUT: offset CPU initialization
				memset (lastKnode, 0, count*sizeof(long));

				// INPUT: offset_2 CPU allocation
				long *offset_2;
				offset_2 = (long *)malloc(count*sizeof(long));
				// INPUT: offset CPU initialization
				memset (offset_2, 0, count*sizeof(long));

				// INPUT: start, end CPU allocation
				int *start;
				start = (int *)malloc(count*sizeof(int));
				int *end;
				end = (int *)malloc(count*sizeof(int));
				// INPUT: start, end CPU initialization
				int i;
				for(i = 0; i < count; i++){
					start[i] = (rand()/(float)RAND_MAX)*size;
					end[i] = start[i]+rSize;
					if(end[i] >= size){ 
						start[i] = start[i] - (end[i] - size);
						end[i]= size-1;
					}
				}

				// INPUT: recstart, reclenght CPU allocation
				int *recstart;
				recstart = (int *)malloc(count*sizeof(int));
				int *reclength;
				reclength = (int *)malloc(count*sizeof(int));
				// OUTPUT: ans CPU initialization
				for(i = 0; i < count; i++){
					recstart[i] = 0;
					reclength[i] = 0;
				}

				// CUDA kernel
				kernel_gpu_opencl_wrapper_2(knodes,
											knodes_elem,
											knodes_mem,

											order,
											maxheight,
											count,

											currKnode,
											offset,
											lastKnode,
											offset_2,
											start,
											end,
											recstart,
											reclength);

			
				pFile = fopen (output,"aw+");
				if (pFile==NULL)
				  {
				    fputs ("Fail to open %s !\n",output);
				  }

				fprintf(pFile,"\n******command: j count=%d, rSize=%d \n",count, rSize);				
				for(i = 0; i < count; i++){
				  fprintf(pFile, "%d    %d    %d\n",i, recstart[i],reclength[i]);
				}
				fprintf(pFile, " \n");
                                fclose(pFile);

				// free memory
				free(currKnode);
				free(offset);
				free(lastKnode);
				free(offset_2);
				free(start);
				free(end);
				free(recstart);
				free(reclength);

				// break out of case
				break;

			}

			// ----------------------------------------40
			// default
			// ----------------------------------------40

			default:
			{

				//usage_2();
				break;

			}

		}
		printf("> ");

	}
	printf("\n");

	// ------------------------------------------------------------60
	// free remaining memory and exit
	// ------------------------------------------------------------60

	free(mem);
	return EXIT_SUCCESS;

}

//========================================================================================================================================================================================================200
//	END
//========================================================================================================================================================================================================200

// # ifdef __cplusplus
// }
// # endif