53.寻宝

n,v = map(int,input().split())
graph = [[10001]*(n+1) for _ in range(n+1)]

# 用邻接矩阵存储各边信息
for i in range(v):
    x,y,z = map(int,input().split())
    graph[x][y] = z
    graph[y][x] = z
visit = [False] *(n+1)
minDist = [10001]*(n+1)

for i in range(1,n+1):
    minval = 10002
    cur = -1
    for j in range(1,n+1): # 找到距离当前节点最近的点
        if visit[j] == False and minDist[j] < minval:
            cur = j
            minval = minDist[j]
    visit[cur] = True
    for k in range(1,n+1): # 把与当前节点相连接的点的距离换成权重值
        if visit[k] == False and graph[cur][k] < minDist[k]:
            minDist[k] = graph[cur][k]
ans = 0
for i in range(2,n+1):
    ans += minDist[i]
print(ans)

53. 寻宝（第七期模拟笔试）