Minimax with alpha-beta pruning
You're X. O searches the whole game tree and can't be beaten. Watch the positions it evaluates, and how many alpha-beta pruning skips.
0evaluated (α-β)
0full search
0%pruned away
Expectimax over a chance node
In 2048 the "opponent" is random, so expectimax averages over outcomes instead of assuming the worst. You've banked 12 this turn — roll once more, or hold?
12value of HOLD
0E[value] of ROLL
HOLDexpectimax says
Breadth-first search — shortest path
BFS explores outward one ring at a time, so it reaches the goal (●) from the start (●) by a shortest path. Draw walls, then run it.
Click or drag to toggle walls.
0cells expanded
—path length