UESTC OJ 1650 Electric System Restore

      这道题和NYOJ上的http://acm.nyist.net/JudgeOnline/problem.php?pid=7非常像，都是找中位数的题目。具体这道题来说，在满足条件的前提下，不断的删除点，由于数据比较小，所以可以直接循环，每次循环的时候删除一个点，若有多个点满足删除的条件，则找最省钱的那个删除即可。

题目地址：http://acm.uestc.edu.cn/problem.php?pid=1650

ac代码：

#include <iostream>
#include <cstdio>
#include <string.h>
#include <algorithm>

using namespace std;
const int N = 1010;
int num[N],px[N],py[N],visted[N];
struct point
{
    int x,y;
}pp[N];

int main()
{
    int numcase,n,m;
    scanf("%d",&numcase);
    for(int k = 1;k <= numcase;++k)
    {
        scanf("%d%d",&n,&m);
        int sum = 0;
        for(int i = 1;i <= n;++i)
        {
            scanf("%d",&num[i]);
        }
       for(int i = 1;i <= n;++i)
       {
           scanf("%d%d",&pp[i].x,&pp[i].y);
       }
       bool flag = true;
       memset(visted,0,sizeof(visted));
       while(m && flag)
       {
           flag = false;
           int numpoint = 0;
           for(int i = 1;i <= n;++i)
           {
               if(!visted[i])
               {
                   px[numpoint] = pp[i].x;
                   py[numpoint++] = pp[i].y;
               }
           }
           sort(px,px+numpoint);
           sort(py,py+numpoint);
           int midx = px[(numpoint-1)/2];
           int midy = py[(numpoint-1)/2];
           //printf("midx= %d midy=%d\n",midx,midy);
           int pos = 0,mm = 0;
           for(int i = 1;i <= n;++i)
           {
               int y = abs(midx - pp[i].x) + abs(midy - pp[i].y);
               if(!visted[i])
               {
                   if(num[i] <= y)
                   {
                       flag = true;
                       if(y - num[i] > mm)
                       {
                           mm = y -num[i];
                           pos = i;
                       }
                   }
               }
           }
           if(flag)
           {
               visted[pos] = 1;
               m--;
               sum += num[pos];
              // printf("pos=%d\n",pos);
           }
       }
       int numpoint = 0;
       for(int i = 1;i <= n;++i)
       {
           if(!visted[i])
           {
               px[numpoint] = pp[i].x;
               py[numpoint++] = pp[i].y;
           }
       }
       sort(px,px+numpoint);
       sort(py,py+numpoint);
       int midx = px[(numpoint-1)/2];
       int midy = py[(numpoint-1)/2];
       for(int i = 1;i <= n;++i)
       {
           if(!visted[i])
           {
               int y = abs(midx - pp[i].x) + abs(midy - pp[i].y);
               sum += y;
           }
       }
       printf("Case #%d: %d\n",k,sum);
    }
    return 0;
}