1. Alpha-Beta Pruning

2. Re-cap Game Theory Design Game Tree
Min-Max Algorithm (aka "Minimax" )  get the value of a node by sending off an accumulator
Depth-limited Min-Max Algorithm
Design
Separation of Concerns

3. Alpha-Beta Pruning
What it does: From root node of a game tree, get the best outcome value of a path
How it does the job
Key assumption: 2 players …

4. Child close over Parent
Inheritance
Inheritance
Child close over Parent

5. Tranverse & Prune AlphaAcc, -1 new AlphaAcc, -Max AlphaAcc, -1
new BetaAcc, Max
b <= a?
BetaAcc, -1
Prune!
new AlphaAcc, -Max
B <= a?
new AlphaAcc, -Max
B <= a?
AlphaAcc, 1
B <= a?
AlphaAcc, -1
B <= a?
B <= a?
BetaAcc,1
BetaAcc, -1
new BetaAcc, Max
new BetaAcc, Max
B <= a?
B <= a?
…..

6. Other OO elements
AlphaBetaFact

7. Goals of presentation – till 8 am
Understand Alpha-Beta Pruning
How the logic of the algorithm drives design of implementation
The logic: 1 hr
Is MinMax
Alpha, Beta inherit max & min accum
Need to compare alpha vs beta in the middle of a alpha-beta recursion
What needs to express in OO: 0.5
Inheritance done
Child closing over parent done