dijstra模板

#include <iostream>
#include<queue>
#include<cstdio>
#include<cstring>
#include<vector>
using namespace std;
const int inf=0x3f3f3f3f;
const int Max=1e4+10;
typedef struct P
{
    int from,cost;//from为父亲节点
    friend operator <(P a,P b){return a.cost<b.cost;}//重载一个判断,使优先队列先取出价值小的//
}P;
typedef struct edge
{
    int to,cost;//to为子节点
}edge;
vector<edge> G[Max];//记录节点之间的关系
int d[105];
int n,m;
void dijk()
{
    fill(d+1,d+n+1,inf);
    priority_queue<P> que;
    d[1]=0;
    P p;
    p.from=1;
    p.cost=0;
    que.push(p);
    while(!que.empty()){
        p=que.top();
        que.pop();
        int v=p.from;
        for(int i=0;i<G[v].size();i++){
            edge e=G[v][i];
            if(d[e.to]>d[v]+e.cost){
                d[e.to]=d[v]+e.cost;
                p.from=e.to;
                p.cost=d[e.to];
                que.push(p);
            }
        }
    }
}
int main()
{
    int u,v,w;
    edge e;
    while(~scanf("%d%d",&n,&m)&&(n||m)){
        for(int i=0;i<1010;++i) G[i].clear();
        memset(d,0,sizeof d);
        for(int i=0;i<m;i++){
            scanf("%d%d%d",&u,&v,&w);
            e.to=v,e.cost=w;
            G[u].push_back(e);
            e.to=u;
            G[v].push_back(e);
        }
        dijk();
        if(d[n]==inf)
            printf("-10086\n");
        else
            printf("%d\n",d[n]);
    }
    return 0;
}