地址 http://poj.org/problem?id=1861
解答 kruscal模板题目 就是输出稍微改下
吐槽下,poj题目的样例居然是错的
// poj1861.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。 // #include <iostream> #include <vector> #include <algorithm> using namespace std; /* 5 8 1 2 5 1 4 2 1 5 1 2 3 6 2 4 3 3 4 5 3 5 4 4 5 6 */ const int N = 15010; const int M = 15010; const int INF = 0x3f3f3f3f; int f[N]; struct EDGE { int a, b, w; }edge[M]; bool cmp(const struct EDGE& a, const struct EDGE& b) { return a.w < b.w; } int find(int x) { return f[x] == x ? x : f[x] = find(f[x]); } int n, m; void kruscal() { int maxlen = -999999; vector<pair<int, int>> ans; sort(edge, edge + m,cmp); for (int i = 1; i <= n; i++) f[i] = i; int cnt = 0; for (int i = 0; i < m; i++) { int a = edge[i].a; int b = edge[i].b; int w = edge[i].w; a = find(a); b = find(b); if (a != b) { f[a] = b; //cout << a << b << endl; maxlen = max(maxlen, w); pair<int, int> tmp = make_pair(edge[i].a, edge[i].b); ans.push_back(tmp); cnt++; } } cout << maxlen << endl; cout << ans.size() << endl; for (int i = 0; i < ans.size();i++) { cout << ans[i].first << " " << ans[i].second << endl; } return; } int main() { cin >> n >> m; for (int i = 0; i < m; i++) { cin >> edge[i].a >> edge[i].b >> edge[i].w; } kruscal(); return 0; }