hdu 1285 拓扑排序（邻接表+邻接矩阵）

/*
	题意：  给N个比赛结果，输出拓扑排名
			

	YY：拓扑排序，初搞，最近练邻接表，感觉比邻接矩阵快的多
		两个都写了一下，竟差两倍之多，邻接表神物啊!!!

*/

//邻接表  	Accepted	1285	15MS	248K	1030 B	C++	kfinder
#include <iostream>
using namespace std;
int ind[505];		// indegree入度个数
int adj[250010];    //adjacency list邻接表位置值
int adj_next[250010];//邻接表下一指针
int tail[505];		//邻接表尾

int main()
{
	int n,m,i,j,a,b;
	while(scanf("%d%d",&n,&m)!=EOF)
	{
		for(i = 0; i <= n; i++) { 
			tail[i] = -1;
			adj[i] = -1;
			adj_next[i] = -1;
			ind[i] = 0;
		}
		for(i = 0; i < m; ++i)
		{
			scanf("%d%d",&a,&b);
			int x = tail[a],flag = 0;
			while(x != -1)  //判断是否重边
			{
				if(adj[x] == b){
					flag = 1;
					break;
				}
				x = adj_next[x];
			}
			if(!flag)//关联a的邻接表
			{
				adj[i] = b;
				adj_next[i] = tail[a];
				tail[a] = i;
				ind[b] ++;
			}
		}
		for(i = 1;i <= n; i++)//找n次
		{
			for(j = 1;j <= n;j++)//遍历
			{
				if(ind[j] == 0){//当入度为0时，说明靠前
					ind[j] = -1;//在下次寻找入度为0时跳过
					//
					if(i == 1)	 printf("%d",j);
					else		 printf(" %d",j);
					//
					for(int k = tail[j]; k != -1; k = adj_next[k])//邻接位置入度减一
					{
						ind[adj[k]] --;
					}
					break;
				}
			}
		}
		printf("\n");
	}
	return 0;
}


//邻接矩阵  Accepted	1285	31MS	1232K	759 B	C++	kfinder
#include <iostream>
using namespace std;
int map[505][505];
int indegree[505];
int n,m;

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