#include <bits/stdc++.h>
using namespace std;

class InParser {
private:
    FILE *fin;
    char *buff;
    int sp;
    
    char read_ch() {
        ++sp;
        if (sp == 4096) {
            sp = 0;
            fread(buff, 1, 4096, fin);
        }
        return buff[sp];
    }
    
public:
    InParser(const char* nume) {
        fin = fopen(nume, "r");
        buff = new char[4096]();
        sp = 4095;
    }
    
    InParser& operator >> (int &n) {
        char c;
        while (!isdigit(c = read_ch()) && c != '-');
        int sgn = 1;
        if (c == '-') {
            n = 0;
            sgn = -1;
        } else {
            n = c - '0';
        }
        while (isdigit(c = read_ch())) {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        return *this;
    }
    
    InParser& operator >> (long long &n) {
        char c;
        n = 0;
        while (!isdigit(c = read_ch()) && c != '-');
        long long sgn = 1;
        if (c == '-') {
            n = 0;
            sgn = -1;
        } else {
            n = c - '0';
        }
        while (isdigit(c = read_ch())) {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        return *this;
    }
} in("ograzi.in");
ofstream out("ograzi.out");

const int CNS = 3541541;
const int MOD = 666013;

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

inline int getHash(int x, int y) {
    return (1LL * x * CNS + y) % MOD;
}

int _w, _h;
bool verify(int p1, int p2, int x, int y) {
    if (p1 < 0 or p2 < 0)
        return false;
    
    int pos = getHash(p1, p2);
    for (pair<int, int> pr : hsh[pos]) {
        if (pr.first <= x and pr.second <= y and
            pr.first + _w >= x and pr.second + _h >= y)
            return true;
    }
    
    return false;
}

int main(void) {
    int n, m, w, h;
    in >> n >> m >> w >> h; _w = w; _h = h;
    
    for (int i = 1; i <= n; ++i) {
        int x, y, p1, p2;
        in >> x >> y;
       
        p1 = x / (w + 1); p2 = y / (h + 1);
        hsh[getHash(p1, p2)].push_back(make_pair(x, y));
    }
    
    int ans = 0;
    for (int i = 1; i <= m; ++i) {
        int x, y, p1, p2; bool ok = false;
        in >> x >> y;
        
        p1 = x / (w + 1); p2 = y / (h + 1);
        for (int q1 = p1 - 1; q1 <= p1 and !ok; ++q1)
        for (int q2 = p2 - 1; q2 <= p2 and !ok; ++q2)
            ok |= verify(q1, q2, x, y);
        
        ans += ok;
    }
    
    out << ans << endl;
    return 0;
}