确定比赛名次

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 11937    Accepted Submission(s): 4753

4 3
1 2
2 3
4 3

1 2 4 3

这题涉及到运算符重载，如果是结构体可以直接用友元函数重载，但是对于内置类型就要换种方法了。

#include <stdio.h>
#include <string.h>
#include <queue>
#include <vector>
#define maxn 502
using namespace std;

bool map[maxn][maxn];
int indegree[maxn], ans[maxn], queue[maxn];

void topSort(int n)
{
	int id = 0, u;
	priority_queue<int, vector<int>, greater<int> > Q;
	for(int i = 1; i <= n; ++i)
		if(!indegree[i]) Q.push(i);
	while(!Q.empty()){
		u = ans[id++] = Q.top(); Q.pop();
		for(int i = 1; i <= n; ++i){
			if(map[u][i] && !--indegree[i])
				Q.push(i);
		}
	}
}

int main()
{
	int n, m, a, b, i;
	while(scanf("%d%d", &n, &m) != EOF){
		memset(map, 0, sizeof(map));
		while(m--){
			scanf("%d%d", &a, &b);
			if(!map[a][b]){
				++indegree[b];
				map[a][b] = 1;
			}
		}
		topSort(n);
		for(i = 0; i < n; ++i)
			if(i != n - 1) printf("%d ", ans[i]);
			else printf("%d\n", ans[i]);
	}
	return 0;
}

HDU1285 确定比赛名次 【拓扑排序】,布布扣,bubuko.com

HDU1285 确定比赛名次 【拓扑排序】

原文：http://blog.csdn.net/chang_mu/article/details/38323499