hdu2544-最短路徑spaf

spaf算法解題

#include<iostream>
#include<queue>
using namespace std;
int g[101][101]={0};
bool is[101] ;
int dis[101];
void spaf(int n,int w)
{
    queue<int> queue;
    queue.push(w);
    memset(is,false,sizeof(is));
    memset(dis,-1,sizeof(dis));
    dis[w] = 0;
    is[w] = true;
    while(!queue.empty())
    {
        int x = queue.front();
        is[x] = false;
        queue.pop();
        for(int i =1;i<=n;i++)
        {
            if(g[x][i] != -1)
            {
            if(dis[i] == -1 || dis[x] + g[x][i] < dis[i])
            {
                dis[i] = dis[x] + g[x][i];
                if(is[i] == false)
                {
                    is[i] = true;
                    queue.push(i);
                }
            }
            }
        }
    }
}
int main()
{
    int n,m,a,b,c;
    while(1)
    {
        memset(g,-1,sizeof(g));
        scanf("%d %d",&n,&m);
        if(n == 0 && m == 0)
        {
            break;
        }
        for(int i = 1;i<=n;i++)
        {
            g[i][i] = 0;
        }
        for(int i =0;i<m;i++)
        {
            scanf("%d %d %d",&a,&b,&c);
            g[a][b] = c;
            g[b][a] = c;
        }
        spaf(n,1);
        printf("%d\n",dis[n]);
    }   
    return 0;
}