#include<bits/stdc++.h>

using namespace std;
using ll = long long;
using pint = pair<int,int>;

#include<atcoder/math>
using namespace atcoder;

//#include"debug.hpp"

int main()
{
	ll N, M, P, Q;
	cin >> N >> M >> P >> Q;
	for(int i = 0; i < Q; i++) {
		ll x, f; cin >> x >> f;
		ll y = inv_mod(x, P) * f;
		y %= P;

		// print(y);
		if(y == 0) {
			cout  << M / P << endl;
		}
		else if(y > M) cout << 0 << endl;
		else cout << (M - y) / P + 1 << endl;;


	}
}