#include <bits/stdc++.h>

using namespace std;
using i64 = int64_t;

int main() {
  i64 N, M, P, Q;
  cin >> N >> M >> P >> Q;
  for (i64 _ = 0; _ < Q; _++) {
    i64 x, f;
    cin >> x >> f;
    i64 begin = -1;
    for (i64 i = 0; P * i + f <= M * x; i++) {
      if (P * i + f != 0 && (P * i + f) % x == 0) {
        begin = (P * i + f) / x;
        break;
      }
      if (i != 0 & f % x == (P * i + f) % x) {
        break;
      }
    }
    if (begin == -1) {
      cout << 0 << endl;
    } else {
      cout << (M - begin) / P + 1 << endl;
    }
  }
  return 0;
}