# AI - lesson 13
#### Francesco Arrigoni
###### December 2015
## Planning pt.2

__Planning:__
- forward planning
- backward planning

__Sequence__:
- initial state
- ACTIONS(g)={relevant and consistent actions for g}
- RESULT(g,a)=R[g,a]
- goal test : $g\subseteq s_0$
- step cost = 1

### Backward Planning

Backward Planning consists in starting from the goal and applying the idea of regression, we are generating other goals.

- __Forward Planning__ is called planning in the *state space*

- __Backward Planning__ is calles planning in the *goal space*,

- Most planners are moving in the *space of plans*.:
    In this type of planning you start from an empty plan and then explore the state of plans

### Title
- reactive
- modeling