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A graph search algorithm that will find theshortest path with some given property, even when the graphcontains cycles. When searching for a path through a graph,starting at a given initial node, where the path (or its endnode) has some desired property, a depth-first search maynever find a solution if it enters a cycle in the graph.Rather than avoiding cycles (i.e. never extend a path with anode it already contains), iterative deepening explores allpaths up to length (or "depth") N, starting from N=0 andincreasing N until a solution is found.