学步园

这是水题：

#include<iostream>
#include<stdio.h>
#include<string.h>
using namespace std;

int main()
{
    int map[101][101];
    int T;
    int index,i,j;
    index=1;
    scanf( "%d",&T );
    while( T-- )
    {
           int n;
           memset( map,0,sizeof(map) );
           scanf( "%d",&n );
           for( i=1;i<=n;i++ )
           for( j=1;j<=n;j++ )
                scanf( "%d",&map[i][j] ); 
           int k;
           int e=n*n-n;
           bool fax=false;
           
           for( i=1;i<=n;i++ )
           for( j=1;j<=n;j++ )
           {
                if( i==j )
                    continue;
                for( k=1;k<=n;k++ )
                {
                     if( i!=k && j!=k )
                     {
                         if( map[i][j]>map[i][k]+map[k][j] )
                         {    
                              fax=true;
                              goto ret;
                         }
                         if( map[i][j]==map[i][k]+map[k][j] )
                         {
                             e--;
                             break;
                         }
                     }
                }    
           }
           ret:
               if( fax )
                   printf( "Case %d: impossible\n",index++ );
               else
                   printf( "Case %d: %d\n",index++,e );
    }
    return 0;
}