HDU 2673 shǎ崽 OrOrOrOrz

#include <cstdio>
#include <algorithm>
using namespace std;
int main()
{
    int n;
    while (scanf("%d",&n)!=EOF)
    {
        int a[];
        for (int i=; i<n; i++)
        scanf("%d",&a[i]);
        sort(a,a+n);
        int begin=,end=n-,flag=;
        printf("%d",a[n-]);
        while (begin<=end)
        {
            if (flag) {printf(" %d",a[begin]); begin++;}
            else {printf(" %d",a[end]); end--;}
            flag^=;
        }
        printf("\n");
    }
    return ;
}