[POJ-2387]Til the Cows Come Home

从V到1可以，从1到V会WA，原因分析中

#include<iostream>#include<cstdio>#include<cstring>#include<string>#include<vector>#include<queue>#include<algorithm>using namespace std;const int MAX_V = 1000 + 5;const int INF = 0xffffff;struct edge{    int to, cost;    edge(int tt, int cc):to(tt), cost(cc) { }};typedef pair<int, int> P;int V;vector<edge> G[MAX_V];int d[MAX_V];void dijkstra( int s ) {    priority_queue< P, vector<P>, greater<P> > que;    fill(d, d+V, INF);    d[s] = 0;    que.push( P(0,s) );    while( !que.empty() ) {        P p = que.top(); que.pop();        int v = p.second;        if( d[v]<p.first ) { continue; }        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;                que.push( P(d[e.to],e.to) );            }        }    }}int main() {    int T, N;    while( cin >> T >> V ) {        while(T--) {            int a, b, c;            cin >> a >> b >> c;            G[a].push_back( edge(b,c) );            G[b].push_back( edge(a,c) );        }        dijkstra( V );        cout << d[1] << endl;    }    return 0;}