Depth First Search -- Backtracking

Problem: Discover a path from start to goal Solution: Begin at start and explore down paths. Whenever there is an unexplored direction, take it. When at a dead end, back up to the first place with unexplored paths. Use a stack S to keep a record of the current path: push onto S as you move forward, pop when backtracking. The process stops when either the S is empty (implying no solution) or when goal = S.top() (implying that the contents of the stack form a solution).