#include <stdio.h>
#include <vector>
using namespace std;

#define LL long long
#define ff first
#define ss second
#define NR 1432131513
#define NRB 47

int N, M, W, H;

int nr1[1 << 18];
pair <int, int> hash1[1 << 18][5];
int nr2[1 << 18];
pair <int, int> hash2[1 << 18][5];

int srch(int x, int y, int md)
{
	int i;

	for (i = 0; i < nr1[md]; i++)
		if (x - W <= hash1[md][i].ff && hash1[md][i].ff <= x && y - H <= hash1[md][i].ss && hash1[md][i].ss <= y) return 1;

	for (i = 0; i < nr2[md]; i++)
		if (x - W <= hash2[md][i].ff && hash2[md][i].ff <= x && y - H <= hash2[md][i].ss && hash2[md][i].ss <= y) return 1;



return 0;
}

int main()
{
	int i, x, y;

	int md;
	
	freopen("ograzi.in", "r", stdin);
	freopen("ograzi.out", "w", stdout);

	scanf("%d %d %d %d", &N, &M, &W, &H);

	for (i = 1; i <= N; i++) {
		scanf("%d %d", &x, &y);

		md = ((LL) (x / W) * (y / H) * NR) >> NRB;

		if (nr1[md] == 5 && nr2[md] == 5) {
			printf("0\n");
			return 0;
		}

		if (nr1[md] <= nr2[md]) hash1[md][nr1[md]++] = make_pair(x, y);
		else hash2[md][nr2[md]++] = make_pair(x, y);
	}

	int ww, hh, rez = 0;

	for (i = 1; i <= M; i++) {
		scanf("%d %d", &x, &y);

		ww = x / W; hh = y / H;

		md = ((LL) ww * hh * NR) >> NRB;
		if (srch(x, y, md)) { rez++; continue; }

		md = ((LL) (ww-1) * hh * NR) >> NRB;
		if (srch(x, y, md)) { rez++; continue; }

		md = ((LL) ww * (hh-1) * NR) >> NRB;
		if (srch(x, y, md)) { rez++; continue; }

		md = ((LL) (ww-1) * (hh-1) * NR) >> NRB;
		if (srch(x, y, md)) { rez++; continue; }
	}

	printf("%d\n", rez);

fclose(stdin);
fclose(stdout);
return 0;
}