数据结构1 - 07-图4 哈利·波特的考试

 

 

#include<stdio.h>
#include<string.h>
#define MAXN 101 
#define INF 0x3fffffff 

int g[MAXN][MAXN],n,m,dist[MAXN],result[MAXN],vis[MAXN];
void read();
void Dijkstra(int s);
int main(){
    read();
    int i,j,maxlen=INF,index=-1;
    memset(result,0,sizeof(result));
    for(i=1;i<=n;i++){
        Dijkstra(i);
        maxlen=0;
        for(j=1;j<=n;j++){
            if(dist[j]==INF) {
                result[i] = INF;
                break;
            }
            if(dist[j]>maxlen && dist[j]!=INF) maxlen = dist[j];
        }
        if(result[i]!=INF){
            result[i] = maxlen;
        }
    }
    maxlen = INF;
    for(i=1;i<=n;i++){
        if(result[i]!=INF && result[i]<maxlen ){
            maxlen = result[i];
            index = i;
        }
    }
    if(index==-1) printf("0\n");
    else printf("%d %d\n",index,maxlen);
    return 0;
}
void read(){
    scanf("%d %d",&n,&m);
    int u,v,w,i,j;
    for(i=1;i<=n;i++)
      for(j=1;j<=n;j++)
         g[i][j] = INF;
    
    for(i=1;i<=m;i++){
        scanf("%d %d %d",&u,&v,&w);
        g[u][v] = w;
        g[v][u] = w;
        
    }
}
void Dijkstra(int s){
    //fill(dist,dist+MAXN,INF);
    //fill(vis,vis+MAXN,0);
    for(int i=1;i<=n;i++)
       dist[i] = INF;
    for(int i=1;i<=n;i++)
       vis[i] = 0;
    int mdata,mindex,i;
    dist[s] =0;
    while(1){
        mdata = INF;
        mindex = -1;
        for(i=1;i<=n;i++){
            if(dist[i]<mdata&&vis[i]==0){
                mdata = dist[i];
                mindex = i;
            }
        }
        if(mindex==-1) break;
        vis[mindex] = 1;
        for(i=1;i<=n;i++){
            if(vis[i]==0&&g[mindex][i]!=INF&&mindex!=i){
                if(dist[mindex]+g[mindex][i]<dist[i]){
                    dist[i] = dist[mindex] + g[mindex][i];
                }
            }
        }
        
    }
}