#include <bits/stdc++.h>

using namespace std;
ifstream f("ograzi.in");
ofstream g("ograzi.out");
const int MaxN = 50005;
unordered_map<pair<int, int>, vector<pair<int, int> > > H;
int n, m, w, h, ans, poz;
pair<int, int> v[MaxN];

inline bool verif(int x, int y) {
    return x >= v[poz].first && x <= v[poz].first + w &&
           y >= v[poz].second && y <= v[poz].second + h;
}

inline void cauta(vector<pair<int, int> > hh) {
    int sz = hh.size();
    for (int i = 0; i < sz; ++i) {
        if (verif(hh[i].first, hh[i].second)) {
            ++ans;
            swap(hh[i], hh[sz - 1]);
            hh.pop_back();
            --sz;
            --i;
        }
    }
}

int main()
{
    f >> n >> m >> w >> h;
    for (int i = 1; i <= n; ++i) {
        int x, y;
        f >> x >> y;
        v[i] = {x, y};
    }
    for (int i = 1; i <= m; ++i) {
        int x, y;
        f >> x >> y;
        H[{x / w, y / h}].push_back({x,  y});
    }
    for (int i = 1; i <= n; ++i) {
        int x = v[i].first, y = v[i].second, b1 = x / w, b2 = y / h;
        poz = i;
        cauta(H[{b1, b2}]);
        cauta(H[{b1 + 1, b2}]);
        cauta(H[{b1, b2 + 1}]);
        cauta(H[{b1 + 1, b2 + 1}]);
    }
    g << ans << '\n';
    return 0;
}