最小生成树采用Prim贪心算法

    MAX = 999  # inf
    
    
    class Start(object):
    def __init__(self, arc, n):
        self.arc = arc  # 邻接矩阵
        self.n = n  # 节点个数
        self.side = self.get_side()
    
    def get_side(self):  # 获取边数
        count = 0
        for i in range(self.n):
            for j in range(i):
                if self.arc[i][j] != 0:   # 如果不是本身（！=0）或者不连接（！=-1）则为一条边