HDU_2544 最短路（Dijkstra）

很裸的最短路径问题，这里用Dijkstra做的，前边已经写过Floyd和SPFA算法

SPFA：http://www.cnblogs.com/vongang/archive/2011/08/16/2141334.html

Floyd：http://www.cnblogs.com/vongang/archive/2011/08/16/2141019.html

My Code：

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;

const int maxnum = 107;
const int inf = 999999;

int dist[maxnum];
int map[maxnum][maxnum];
int vis[maxnum];
int n, m;

void Dijkstra()
{
    int i, j;
    memset(vis, 0, sizeof(vis));
    for(i = 1; i <= n; i++)
    {
        dist[i] = map[1][i];
        vis[i] = 0;
    }
    dist[1] = 0;
    vis[1] = 1;
    for(i = 2; i <= n; i++)
    {
        int flag, min = inf;
        for(j = 1; j <= n; j++)
            if(!vis[j] && dist[j] < min)
            {
                flag = j;
                min = dist[j];
            }
        vis[flag] = 1;
        for(j = 1; j <= n; j++)
            if(!vis[j] && map[flag][j] < inf)
            {
                int newdist = dist[flag] + map[flag][j];
                if(newdist < dist[j])
                    dist[j] = newdist;
            }
    }
}
int main()
{
    //freopen("data.in", "r", stdin);
    int i, j, a, b, c;
    while(scanf("%d%d", &n, &m), n||m)
    {
        for(i = 1; i <= n; i++)
            for(j = 1; j <= n; j++)
                map[i][j] = inf;
        while(m--)
        {
            scanf("%d%d%d", &a, &b, &c);
            if(c < map[a][b])
                map[a][b] = map[b][a] = c;
        }
        Dijkstra();
        printf("%d\n", dist[n]);
    }
    return 0;
}