#include <bits/stdc++.h>   using namespace std;   const inline int __GET_INT() {     int ret;     scanf( %d , &ret);     return ret;   }   int main() {     long long A = __GET_INT(), B = __GET_INT(), n = __GET_INT();     for (int i = 0; i < n; ++i) {       long long l = __GET_INT(), t = __GET_INT(), m = __GET_INT();       long long first = B * (l - 1) + A;       if (first > t) {         puts( -1 );       } else {         int r = -1;         long long low = 1, high = 1000000, mid;         while (low <= high) {           mid = (low + high) >> 1;           long long val = ((mid * (mid - 1)) / 2) * B + mid * first;           long long second = B * (l + mid - 2) + A;           if (second > t || val > (t * m)) {             high = mid - 1;           } else {             low = mid + 1;             r = l + mid - 1;           }         }         printf( %d n , r);       }     }     return 0;   }   