#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <complex>
#include <cstdio>
#include <deque>
#include <functional>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#define REP(i, N) for (int i = 0; i < (int)N; i++)
#define FOR(i, a, b) for (int i = a; i < (int)b; i++)
#define ALL(x) (x).begin(), (x).end()

using namespace std;

constexpr int inf = 1 << 30;
constexpr long long llinf = 1LL << 62;
constexpr int mod = 998244353;  // 1000000007;

using ll = long long;

namespace phc {
long long modpow(long long a, long long n) {
  long long res = 1;
  while (n > 0) {
    if (n & 1) res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}
long long modinv(long long a, long long m) {
  long long b = m, u = 1, v = 0;
  while (b) {
    long long t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= m;
  if (u < 0) u += m;
  return u;
}
long long gcd(long long a, long long b) { return b != 0 ? gcd(b, a % b) : a; }
long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
}  // namespace phc

int main() {
  ll N, M, P, Q;
  cin >> N >> M >> P >> Q;
  REP(i, Q) {
    ll x, f;
    cin >> x >> f;
    if (x % P == 0) {
      cout << (f == 0 ? M : 0LL) << endl;
    } else {
      ll y = f * phc::modinv(x, P) % P;
      cout << ((M - y + (f != 0 ? P : 0LL)) / P) << endl;
    }
  }
  return 0;
}