Node
Parameters
puzzleStatePair
Current puzzle state (flattened into one dimension, following row-major order) and the position of the blank tile in the puzzle grid (zero-based, following row-major order).
parent
Parent of this node (null if this is the start node).
g
Cost of the path from the start node to this node (depth of this node).
h
Heuristic for estimating the cheapest path from this node to the goal (Manhattan distance).