#include <string.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <ciso646>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <optional>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#define REP_OVERLOAD(arg1, arg2, arg3, arg4, NAME, ...) NAME
#define REP3(i, l, r, s)                                               \
    for (int i = int(l), rep3_r = int(r), rep3_s = int(s); i < rep3_r; \
         i += rep3_s)
#define REP2(i, l, r) REP3(i, l, r, 1)
#define REP1(i, n) REP2(i, 0, n)
#define rep(...) REP_OVERLOAD(__VA_ARGS__, REP3, REP2, REP1, )(__VA_ARGS__)
#define repin(i, l, r) for (int i = int(l), repin_r = int(r); i <= repin_r; ++i)

#define RREP_OVERLOAD(arg1, arg2, arg3, arg4, NAME, ...) NAME
#define RREP3(i, l, r, s)                                                      \
    for (int i = int(r) - 1, rrep3_l = int(l), rrep3_s = int(s); i >= rrep3_l; \
         i -= rrep3_s)
#define RREP2(i, l, r) RREP3(i, l, r, 1)
#define RREP1(i, n) RREP2(i, 0, n)
#define rrep(...) RREP_OVERLOAD(__VA_ARGS__, RREP3, RREP2, RREP1, )(__VA_ARGS__)
#define rrepin(i, l, r) \
    for (int i = int(r), rrepin_l = int(l); i >= rrepin_l; --i)

#define fi first
#define se second

#include <atcoder/math>

#include <algorithm>
#include <cassert>
#include <vector>

namespace rklib {

template <class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

template <class T>
bool chmin(T &a, const T &b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}

template <class T>
bool chmin_non_negative(T &a, const T &b) {
    if (a < 0 || a > b) {
        a = b;
        return true;
    }
    return false;
}

template <class T>
T div_floor(T num, T den) {
    if (den < 0) num = -num, den = -den;
    return num >= 0 ? num / den : (num + 1) / den - 1;
}

template <class T>
T div_ceil(T num, T den) {
    if (den < 0) num = -num, den = -den;
    return num <= 0 ? num / den : (num - 1) / den + 1;
}

}  // namespace rklib


using namespace std;
using namespace rklib;

using lint = long long;
using pii = pair<int, int>;
using pll = pair<lint, lint>;

int main() {
    lint n, m, p, q;
    scanf("%lld%lld%lld%lld", &n, &m, &p, &q);

    rep(qq, q) {
        lint x, f;
        scanf("%lld%lld", &x, &f);

        if (x % p == 0) {
            printf("%lld\n", f == 0 ? m : 0);
        } else {
            auto t = atcoder::inv_mod(x, p) * f % p;
            if (t == 0) {
                printf("%lld\n", m / p);
            } else {
                printf("%lld\n", t > m ? 0 : (m - t) / p + 1);
            }
        }
    }
}