POJ 3723 Conscription 并查集 + Kruskal

#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;

#define MAX_N 20002
#define MAX_E 50001

struct edge{
	int u, v, cost;
};

int par[MAX_N];
int Rank[MAX_N];

edge es[MAX_E];
int V, E;

bool compare(const edge &e1, const edge &e2)
{
	return e1.cost<e2.cost;
}

void init(int N)
{
	for (int i = 0; i<N; i++)
	{
		par[i] = i;
		Rank[i] = 0;
	}
}

int find(int x)
{
	if (par[x] == x)
		return x;
	else
		return par[x]=find(par[x]);
}

void unite(int x, int y)
{
	x = find(x);
	y = find(y);
	if (x == y) return;
	if (Rank[x]>Rank[y])
		swap(x, y);
	par[x] = y;
	Rank[x]++;
}

bool same(int x, int y)
{
	x = find(x);
	y = find(y);
	return x == y;
}

int krus()
{
	sort(es, es + E, compare);
	init(V);
	int ret = 0;
	for (int i = 0; i<E; i++)
	{
		if (same(es[i].u, es[i].v) == false)
		{
			ret += es[i].cost;
			unite(es[i].u, es[i].v);
		}
	}
	return ret;
}

int main()
{
	int count;
	int N, M;
	scanf("%d", &count);
	for (int i = 0; i<count; i++)
	{
		scanf("%d%d%d", &N, &M, &E);
		for (int j = 0; j<E; j++)
		{
			int v, cost;
			scanf("%d%d%d", &es[j].u, &v, &cost);
			es[j].v = v + N;
			es[j].cost = -cost;
		}
		V = M + N;
		printf("%d\n", V * 10000 + krus());
	}
	return 0;
}