#include <iostream>
#include <fstream>
#include <vector>
using namespace std;

ifstream fin("ograzi.in");
ofstream fout("ograzi.out");

#define MOD 999993

int N, M, W, H;

vector< pair<int, int> > HASH[MOD];

int get_key(int x, int y) {
    return (1LL * x * 9132123 + y) % MOD;
}

int main () {
    fin >> N >> M >> W >> H;

    for (int i = 1; i <= N; ++i) {
        int x, y;
        fin >> x >> y;
        HASH[get_key(x / W, y / H)].push_back(make_pair(x, y));
    }

    int rez = 0;

    for (int i = 1; i <= M; ++i) {
        int x, y;
        fin >> x >> y;

        int ok = 0;

        for (int dx = -1; dx <= 0 && !ok; ++dx)
            for (int dy = -1; dy <= 0 && !ok; ++dy) {
                int key = get_key(x / W + dx, y / H + dy);
                for (int j = 0; j < HASH[key].size() && !ok; ++j) {
                    int cx = HASH[key][j].first;
                    int cy = HASH[key][j].second;
                    if (x >= cx && x <= cx + W)
                        if (y >= cy && y <= cy + H) {
                            ++rez;
                            ok = 1;
                        }
                }
            }
     }

    fout << rez;

    return 0;
}