#include <stdio.h>
#include <stdlib.h>

const int Mod = 1000000007;
long long fact[2000001], fact_inv[2000001];

long long div_mod(long long x, long long y, long long z)
{
	if (x % y == 0) return x / y;
	else return (div_mod((1 + x / y) * y - x, (z % y), y) * z + x) / y;
}

long long combination(int n, int k)
{
	return fact[n] * fact_inv[k] % Mod * fact_inv[n-k] % Mod;
}

int main()
{
	int A, B, X, Y;
	scanf("%d %d %d %d", &A, &B, &X, &Y);
	if (abs(X + Y) % 2 != A % 2 || abs(X) + abs(Y) > A) {
		printf("0\n");
		fflush(stdout);
		return 0;
	}
	if (B == 0) {
		if (X == A && Y == 0) printf("1\n");
		else printf("0\n");
		fflush(stdout);
		return 0;
	} else if (B == 1) {
		if (X >= 0 && Y >= 0 && X + Y == A) printf("1\n");
		else printf("0\n");
		fflush(stdout);
		return 0;
	} else if (B == 2) {
		if (Y >= 0) printf("1\n");
		else printf("0\n");
		fflush(stdout);
		return 0;
	}

	int i;
	for (i = 1, fact[0] = 1; i <= A + B; i++) fact[i] = fact[i-1] * i % Mod;
	for (i = A + B - 1, fact_inv[A+B] = div_mod(1, fact[A+B], Mod); i >= 0; i--) fact_inv[i] = fact_inv[i+1] * (i + 1) % Mod;

	int r, l, u, d, sur = (A - abs(X) - abs(Y)) / 2;
	long long ans = 0;
	for (i = 0; i <= sur; i++) {
		if (X >= 0) {
			r = X + i;
			l = i;
		} else {
			r = i;
			l = -X + i;
		}
		if (Y >= 0) {
			u = Y + sur - i;
			d = sur - i;
		} else {
			u = sur - i;
			d = -Y + sur - i;
		}
		ans += combination(r + B / 4, r) * combination(u + (B - 1) / 4, u) % Mod * combination(l + (B - 2) / 4, l) % Mod * combination(d + (B - 3) / 4, d) % Mod;
	}
	printf("%lld\n", ans % Mod);
	fflush(stdout);
	return 0;
}