#include <bits/stdc++.h>
#include <atcoder/all>
using ll = long long;
#define MOD 1000000007
#define Mod 998244353
const int MAX = 1000000005;
const long long INF = 1000000000000000005LL;
using namespace std;
using namespace atcoder;

ll modpow(ll a, ll n, ll m) {
	ll res = 1;
	while (n > 0) {
		if (n & 1) res = res * a % m;
		a = a * a % m;
		n >>= 1;
	}
	return res;
}

ll modinv(ll a, ll m) {
	return modpow(a, m-2, m);
}

int main() {
    ios::sync_with_stdio(0);cin.tie();
    int N, M, P, Q;
    cin >> N >> M >> P >> Q;
    while (Q--) {
        int x, f;
        cin >> x >> f;
        int a = modinv(x, P) * f % P;
        if (M < a) {
            cout << 0 << endl;
        } else {
            cout << (M - a)/P + 1 - (a == 0) << endl;
        }
    }
}