need help to debug my code for QHOUSE february lunctime…

solution for subtask submitted successfully here is the link

but this submission for 100 is not going in that way…

I need help to debug this code…

Any help will be greatly appreciated…

The mistake is where you write


for 2^{nd} binary search (line 74).

It should be start=rect.x/2 because you have already multiplied rect.x by 2 and binary search should start from

x coordinate=side_of_square/2.

corrected solution


Can someone please say where I am going wrong ? I am not finding any probable errors :frowning:


The problem is where you return mid at the each binary search function.
It should instead be:

    cout << "? " << 0 <<" "<< high << "\n";
    cin >> s;
    if(s[0] == 'Y')
    {return high;}

    cout << "? " << 0 <<" "<< low << "\n";
    cin >> s;
    if(s[0] == 'Y')
    {return low;}

    return mid;

because it is not necessary that mid has the correct answer.

Similarly for each binary search function.

Here is the corrected solution.

Also, why have you made array a when a[i]=i ?

There was one more error in line 37 of the link which you have given.

It was written a[mid+1] instead of a[mid].
It took a lot of time to find this one.


sorry for posting my question through the answer…but i m a beginner and donot hav enough karma for posting the questions…someone please check my code and please point my error…please…it would be of great help…

You should give codechef submission link.

I suggest you should read the editorial and see setter’s solution.

Thank You so much… just missed that thing… It was difficult to make valid testcase for this question…
Thanks a lot…

Thanks a lot , for helping me out spending your important time. I’m grateful to you friend. :slight_smile:
There is no link for the editorial on the problem’s page…please help with my code…