Floyd算法

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#-*- coding: cp936 -*- -*-from sys import maxintclass shortestPath:    @staticmethod    def floyd(node,connected,path):        for i in range(len(node)):            for j in range(len(node)):                if connected[i][j]<maxint:                    path[i][j][i]=True                    path[i][j][j]=True        for u in range(len(node)):#中间顶点的序号从 0 到 n-1            for v in range(len(node)):                for w in range(len(node)):                    if connected[v][u]+connected[u][w] < connected[v][w]:                        connected[v][w]=connected[v][u]+connected[u][w]                        for t in range(len(node)):                            path[v][w][t] = path[v][u][t] or path[u][w][t]        shortestPath.printPath(node,connected,path)    @staticmethod    def printPath(node,connected,path):        for i in range(len(node)):            for j in range(len(node)):                if i == j:                    continue                print("------------------------")                throughNode=[]                for t in range(len(node)):                    if path[i][j][t]:                        throughNode.append((connected[i][t],t))                throughNode.sort(key=lambda tup:tup[0])                if connected[i][j]==maxint:                    print(node[i]+" and "+node[j]+" not connected")                else:                    print(node[i]+"->"+node[j]+" cost "+str(connected[i][j]))                    print("path is ...")                    for each in throughNode:                        print(node[each[1]])def main():    #使用邻接矩阵来表示图    node = ['V0','V1','V2','V3','V4','V5']    connected = [[maxint,maxint,    10,maxint,30,       100],                 [maxint,maxint,     5,maxint,maxint,maxint],                 [maxint,maxint,maxint,    50,maxint,maxint],                 [maxint,maxint,maxint,maxint,maxint,    10],                 [maxint,maxint,maxint,    20,maxint,    60],                 [maxint,maxint,maxint,maxint,maxint,maxint]]    #path[i][j][k]为True表示 k 是 i到j 当前最短路径 的一个点    path = [[[False for i in range(len(node))] for j in range(len(node))] for k in range(len(node))]    shortestPath.floyd(node,connected,path)    if __name__=='__main__':    main()
结果截图：
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