John is going on a fishing trip. He has h hours available (1 <= h <= 16), and there are n lakes in the area (2 <= n <= 25) all reachable along a single, one-way road. John starts at lake 1, but he can finish at any lake he wants.。。。。Write

Petri网可达分析算法，将Petri网的关联矩阵输入，得到该可达分析图的性质-Petri net reachability analysis algorithm, the Petri net associative matrix input, get the nature of the reachable analysis