A

#include <bits/stdc++.h>

using namespace std;

#define ll     long long
#define _test   int _TEST; cin>>_TEST; while(_TEST--)

int main()
{
    _test
    {
        int n, x, k;
        cin>>n>>x>>k;

        n -= x;

        n %= k;
        x %= k;

        cout<<max(n, x) - min(n, x)<<"\n";
    }
}