#include <bits/stdc++.h>
using namespace std;
int n, m, l, r;

int dis[1010][1010] = {0};
long long ans = 0;
int gcd(int x, int y) {
	if (y == 0)
		return x;
	return gcd(y, x % y);
}

int main() {
	freopen("rockboard.in", "r", stdin);
	freopen("rockboard.out", "w", stdout);
	cin >> n >> m >> r >> l;
	l *= l;
	r *= r;
	for (int i = 0; i <= n; i++) {
		for (int j = 0; j <= m; j++) {
			if (gcd(i, j) == 1) {
				dis[i][j] = i * i + j * j;
				if (dis[i][j] < r || dis[i][j] > l)
					dis[i][j] = 0;
			}
		}
	}
	if (r <= 1 && l >= 1)
		ans += (n + 1) * m + (m + 1) * n;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			if (dis[i][j] != 0) {
				ans += n * m * 2 - (i - 1) * m *  2 - (j - 1) * n  * 2;
			}
		}
	}
	cout << ans << endl;
	return 0;
}