depth-first search (algorithm) A graph search algorithm which extends the current path as far as possible before backtracking to the last choice point and trying the next alternative path. Depth-first search may fail to find a solution if it enters a cycle in the graph. This can be avoided if we never extend a path to a node which it already contains.
Opposite of breadth first search. See also iterative deepening. Last updated: 1995-04-19