POJ_2388_Who's in the Middle(快排)

# include<stdio.h>
# include <string.h>
# include <algorithm>
using namespace std;
bool comp(int a,int b)
{
    return a>b;
}
int main()
{
    int n,i;
    int a[10005];
    scanf("%d",&n);
    for(i=0;i<n;i++)
    {
        scanf("%d",&a[i]);
    }
    sort(a,a+n,comp);
    if(n%2 == 0 )
        printf("%d\n",(a[n/2-1]+a[n/2])/2);
    else 
        printf("%d\n",a[n/2]);
    return 0;
}