POJ 2387 Til the Cows Come Home

题意：给一个无向图，求从点1到n的最短路。

 

解法：dijkstra。灰常裸……

 

代码：

#include<stdio.h>
#include<iostream>
#include<algorithm>
#include<string>
#include<string.h>
#include<math.h>
#include<limits.h>
#include<time.h>
#include<stdlib.h>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<vector>
#define LL long long
using namespace std;
struct node
{
    int v, val;
    node(int v, int val) : v(v), val(val) {}
    node() {}
};
vector <node> edge[1005];
int dis[1005];
bool vis[1005];
const int inf = 0x3f3f3f3f;
int main()
{
    int n, m;
    while(~scanf("%d%d", &m, &n))
    {
        memset(dis, inf, sizeof dis);
        memset(vis, 0, sizeof vis);
        for(int i = 0; i < m; i++)
        {
            int a, b, c;
            scanf("%d%d%d", &a, &b, &c);
            edge[a].push_back(node(b, c));
            edge[b].push_back(node(a, c));
            if(a == 1)
                dis[b] = min(dis[b], c);
            if(b == 1)
                dis[a] = min(dis[a], c);
        }
        dis[1] = 0;
        vis[1] = 1;
        while(1)
        {
            int pos = -1, minn = inf;
            for(int i = 1; i <= n; i++)
            {
                if(!vis[i] && minn > dis[i])
                {
                    pos = i;
                    minn = dis[i];
                }
            }
            if(pos == -1)
                break;
            vis[pos] = 1;
            int len = edge[pos].size();
            for(int i = 0; i < len; i++)
            {
                int u = edge[pos][i].v;
                dis[u] = min(dis[u], dis[pos] + edge[pos][i].val);
            }
        }
        printf("%d\n", dis[n]);
    }
    return 0;
}