zoj2008 最短路

#include<cstdio>
#include<cstring>
#include<queue>
#include<algorithm>
const int maxn = 1000009;
const int inf = 1<<30;
#include<vector>
struct node
{
	int v,w;
	node(int v,int w):v(v),w(w){}
	bool operator < (const node a)const
	{
		return w > a.w;
	}
};
std::vector<node> eg[maxn];
std::priority_queue<node> q;
int n,m;
int vis[maxn];
int dis[maxn];
int a[maxn],b[maxn],c[maxn];

void DIJ()
{
	int i;
	memset(vis,0,sizeof(vis));
	for(i=0;i<=n;i++)
		dis[i] = inf;
	while(!q.empty())q.pop();
	dis[1] = 0;
	vis[1] = 0;
	int size = eg[1].size();
	for(i=0; i < size; i++)
	{
		q.push(node(eg[1][i].v,eg[1][i].w));
		dis[eg[1][i].v] = eg[1][i].w;
	}
	while(!q.empty())
	{
		int u = q.top().v;
		int w = q.top().w;
		q.pop();
		if(!vis[u])
		{
			vis[u] = 1;
			size = eg[u].size();
			for(i=0; i<size; i++)
			{
				int v = eg[u][i].v;
				int w = eg[u][i].w;
				if(!vis[v] && dis[u] + w < dis[v])
				{
					dis[v] = dis[u] + w;
					q.push(node(v,dis[v]));
				}
			}
		}
	}
	
}
void work()
{
	int i,sum = 0;
	DIJ();
	for(i=2; i<=n; i++)   sum += dis[i]; //printf("%d ",dis[i]);}
	for(i=0; i<=n; i++) eg[i].clear();
	for(i=0;i<m;i++)    eg[b[i]].push_back(node(a[i],c[i]));
  //  printf("\n");
	DIJ();
	for(i=2; i <= n;i++) sum += dis[i]; //printf("%d ",dis[i]);}
	printf("%d\n",sum);
}
void input()
{
	int i;
	scanf("%d%d",&n,&m);
	for(i=0 ;i < m; i++)  scanf("%d%d%d",&a[i],&b[i],&c[i]);
	for(i=0;i<=n;i++)     eg[i].clear();
	for(i=0;i<m;i++)      eg[a[i]].push_back(node(b[i],c[i]));
}
int main()
{
	int t;
	scanf("%d",&t);
	while(t--)
	{
		input();		
		work();
	}
	return 0;
}



/*

3
2 2
1 2 13
2 1 33
4 6
1 2 10
2 1 60
1 3 20
3 4 10
2 4 5
4 1 50
2 2
1 2 13
2 1 33

  */