学步园

擦，没有判重边wa了两发。。

#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <queue>
#include <algorithm>

using namespace std;

const int maxn = 1010;
const int inf = 0x3f3f3f3f;
bool vis[maxn];
int map[maxn][maxn];
int dis[maxn];
int n, m;

void dijkstra(int start)
{
        dis[start] = 0;
        int now, mindis;
        for(int i = 0; i < n; i++)
        {
                mindis = inf;
                for(int j = 0; j < n; j++)
                {
                        if(!vis[j] && mindis > dis[j])
                        {
                                mindis = dis[j];
                                now = j;
                        }
                }
                if(mindis >= inf)
                        break;
                vis[now] = true;
                for(int j = 0; j < n; j++)
                {
                        if(!vis[j] && dis[now] + map[now][j] < dis[j])
                                dis[j] = dis[now] + map[now][j];
                }
        }
}

int main()
{
        #ifdef BellWind
        freopen("1874.in", "r", stdin);
        #endif // BellWind

        while(~scanf("%d%d", &n, &m))
        {
                int a, b, cost;
                int s, e;
                memset(vis, false, sizeof(vis));
                memset(map, 0x3f, sizeof(map));
                memset(dis, 0x3f, sizeof(dis));
                for(int i = 0; i < m; i++)
                {
                        scanf("%d%d%d", &a, &b, &cost);
                        if(cost < map[a][b])
                        {
                                map[a][b] = cost;
                                map[b][a] = cost;
                        }
                }
                scanf("%d%d", &s, &e);
                dijkstra(s);
                if(dis[e] >= inf)
                        printf("-1\n");
                else
                        printf("%d\n", dis[e]);
        }

        return 0;
}