POJ 3723

最大生成树

#include<iostream>
#include<cstdio>
#include<cstring>
#include<set>
#include<algorithm>
#include<stack>
#include<map>
#include<queue>
#include<list>
#include<vector>
using namespace std;
const int maxn = 50000 + 131;
const int maxm = 10000 + 131;
struct Edge {
    int u, v, cost;
    Edge(int u_, int v_, int c_): u(u_), v(v_), cost(c_) {}
    bool operator < (const Edge a) const {
        return cost > a.cost;
    }
};
vector<Edge> G;

/// Uinon-Set
int Pre[maxm * 2], Num[maxm * 2];
void Init(int N) {
    for(int i = 0; i <= N; ++i)
        Pre[i] = i;
}

int Find(int x) {
    /*int r = x;
    while(r != Pre[r]) r = Pre[r];
    return Pre[x] = r;*/
    if(x == Pre[x]) return x;
    else return Pre[x] = Find(Pre[x]);
}

bool Union(int x, int y) {
    int ax = Find(x), ay = Find(y);
    if(ax == ay) return false;
    Pre[ax] = ay;
    return true;
}

/// MST;
typedef long long LL;
LL Sum = 0;
LL Kusual(int N,int R)
{
    Sum = 0;
    sort(G.begin(),G.end());
    Init(N);
    for(int i = 0; i < G.size(); ++i)
    {
        int u = G[i].u, v = G[i].v;
        if(Union(u, v))
        {
            Sum +=(LL) (G[i].cost);
        }
    }
    return Sum;
}

int main()
{
    int N, M, R;
    int x, y, d;
    int T;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d%d", &N, &M, &R);
        G.clear();
        for(int i = 0; i < R; ++i)
        {
            scanf("%d%d%d", &x, &y, &d);
            G.push_back(Edge(x,y+N,d));
            G.push_back(Edge(y+N,x,d));
        }
        //cout << Sum << endl;
        //Sum = 0;
        printf("%lld
",(LL)(10000 * (N+M)) - Kusual(N+M,R));
    }
}