dij模板

#include<cstdio>
#include<vector>
#include<queue>
using namespace std;
struct edge
{
	int to,val;
};
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > >q;
vector<edge>e[2505];
int dis[2505];
int vis[2505];
int main()
{
	int n,m;
	scanf("%d%d",&n,&m);
	for(int i=1;i<=m;i++)
	{
		int x,y,z;
		scanf("%d%d%d",&x,&y,&z);
		edge tmp;
		tmp.to=y;
		tmp.val=z;
		e[x].push_back(tmp);
		tmp.to=x;
		tmp.val=z;
		e[y].push_back(tmp);
	}
	for(int i=1;i<=n;i++)
	{
		dis[i]=2147483647;
	}
	dis[1]=0;
	q.push(make_pair(0,1));
	while(!q.empty())
	{
		int x=q.top().second;
		q.pop();
		if(vis[x]==1)
		continue;
		vis[x]=1;
		for(int i=0;i<e[x].size();i++)
		{
			int y=e[x][i].to;
			if(dis[x]+e[x][i].val<dis[y])
			{
				dis[y]=dis[x]+e[x][i].val;
				q.push(make_pair(dis[y],y));
			}
		}
	}
	printf("%d\n",dis[n]);
	return 0;
}