void ksort(int *num, int low, int hig)
{
    if (hig<low+2) return ;
    int e = hig, p = low;
    if (low<hig)
    {
        while ((++low<e) && (num[low] <= num[p]));
        while ((--hig>p) && (num[hig] >= num[p]));
        if (low<hig) swap(num[low], num[hig]);
    }
    swap(num[hig], num[p]);
    ksort(num, p, hig);
    ksort(num, low, e);
}