Q11369: Shopaholic

原文

http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=2354

中譯

http://luckycat.kshs.kh.edu.tw/homework/q11369.htm

#include "stdio.h"

int quicksort(int p[],int left,int right)
{
  if( left >= right )
 return 0;
  int i,j,s,tmp;
  s = p[left];
  i = left + 1;
  j = right;
  while( 1 )
  {
    while( i < right && p[i] >= s )
   i++;
 while( j > left && p[j] <= s )
   j--;
 if( i >= j )
   break;
 tmp = p[i];
 p[i] = p[j];
 p[j] = tmp;
  }
  tmp = p[left];
  p[left] = p[j];
  p[j] = tmp;
  quicksort(p,left,j - 1);
  quicksort(p,j + 1,right);
  return 0;
}
int main()
{
  int num;
  scanf(" %d",&num);
  while( num-- )
  {
 int i,j,n,p[20000]={0},save = 0,tmp;
 scanf(" %d",&n);
 for(i = 0;i < n;i++)
 {
   scanf(" %d",&p[i]);
 }
 quicksort(p,0,n - 1);
 for(i = 2;i < n;i+=3)
 {
  save += p[i];
 }
 printf("%d\n",save);
  }
  return 0;
}