uva 10600

最小生成树和次小生成树的裸题

#include <bits/stdc++.h>
using namespace std;

const int INF = 1000000000;
const int maxn = 100 + 10;

int T,n,m,ans,ans2,p[maxn],fa[maxn];
struct node {
    int a, b, c;
    bool operator < (const node& rhs) const {
        return c < rhs.c;
    }
}a[maxn*maxn];
vector<node> g;
int _find(int x, int p[]) { return p[x] == x ? x : p[x] = _find(p[x], p); }
void solve() {
    sort(a, a+m);
    int cnt = 1;
    ans = 0;
    g.clear();
    for(int i=1;i<=n;i++) p[i] = i;
    for(int i=0;i<m;i++) {
        int x = _find(a[i].a, p), y = _find(a[i].b, p);
        if(x != y) {
            p[x] = y;
            g.push_back(a[i]);
            ++cnt;
            ans += a[i].c;
        }
        if(cnt == n) break;
    }
    ans2 = INF;
    for(int i=0;i<g.size();i++) {
        node v = g[i];
        int cur = 0, cnt = 1;
        for(int j=1;j<=n;j++) fa[j] = j;
        for(int j=0;j<m;j++) {
            if(v.a == a[j].a && v.b == a[j].b && v.c == a[j].c) continue;
            int x = _find(a[j].a, fa), y = _find(a[j].b, fa);
            if(x != y) {
                fa[x] = y;
                ++cnt;
                cur += a[j].c;
            }
            if(cnt == n) break;
        }
        if(cnt == n) ans2 = min(ans2, cur);
    }
}
int main() {
    scanf("%d",&T);
    while(T--) {
        scanf("%d%d",&n,&m);
        for(int i=0;i<m;i++) scanf("%d%d%d",&a[i].a,&a[i].b,&a[i].c);
        solve();
        printf("%d %d\n",ans,ans2);
    }
    return 0;
}