what is test 3?
this is my program
#include <iostream.h>
#include <fstream.h>
#include <math.h>


int i,h,n,k;

int main()
{
    cin >> n;
    for (i=1;i<=n;i++)
    {
        cin >> k;
        h=ceil(sqrt((double)((k-1)*2)));
        if (h*(h-1)/2 + 1==k) cout << 1 << ' '; else cout << 0 << ' ';
    }
    return 0;
}
dont know why it is wrong answer

Probably
(k - 1) * 2
causes integer overflow, the same is for
h * (h - 1)
Try
(double(k - 1)) * 2
and
int(double(h) * (h - 1) / 2 + 1)
or something like that.

Many thanks
It works well

Edited by author 22.10.2006 16:01

Edited by author 22.10.2006 16:02