poj 1258 Agri-Net

一道简单的最小生成树问题：

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cmath>
#include<queue>
#include<map>
#include<cstring>
#include<vector>
using namespace std;
class Kru
{
public:
      int x,y,dis;
}kru[10024];
int set[124];
bool cmp(Kru a , Kru b )
{
    return a.dis < b.dis;    
}
int find( int x )
{
   return set[x] == x ? x : set[x] = find( set[x] );    
}
int Kruscal( int N )
{
  int ans=0,X,Y;
  for( int i = 0 ; i < N ; i++ )
  {
     if( ( X = find( kru[i].x ) )!=( Y = find(kru[i].y) ) )
     {
         ans += kru[i].dis;
         set[Y] =X;        
     }
  }    
  return ans;
}
int main(  )
{
     int N,dis;
     while( scanf( "%d",&N )==1 )
     {
         int count = 0 ;
         for( int i = 1 ; i <= N ; i++ )
         {
            set[i] = i;
            for( int j = 1 ; j <= N; j ++ )
            {
                 scanf( "%d",&dis );
                 kru[count].x = i;kru[count].y=j;
                 kru[count++].dis = dis;    
            }    
         }
         sort( kru ,kru + count , cmp );
         printf( "%d\n",Kruscal( count ) );            
     }
    //system( "pause" );
    return 0;
}