a,b,x,y = map(int,input().split())
mod = 10**9+7

### for bigger prime 
fact = [1,1]
finv = [1,1]
inv = [0,1]
 
for i in range(2,2*10**6+5):
    fact.append((fact[-1]*i)%mod)
    inv.append((inv[mod%i]*(mod-mod//i))%mod)
    finv.append((finv[-1]*inv[-1])%mod)
 
def nCr(n,r,mod):
    if r > n:
        return 0
    else: 
        return fact[n]*finv[r]%mod*finv[n-r]%mod


ans = 0
r = (b+4)//4
u = (b+3)//4
l = (b+2)//4
d = (b+1)//4

for i in range(a+1):
    if i < x:
        continue
    dif = i-x
    left = a-i-dif
    if l == 0:
        base = nCr(i+r-1,i,mod)
    else:
        base = nCr(i+r-1,i,mod)*nCr(dif+l-1,dif,mod)%mod

    if left < abs(y):
        continue
    if y >= 0:
        left -= y
        if left%2:
            continue
        need = y+left//2
    else:
        left += y
        if left%2:
            continue
        need = -y+left//2
    if r == 0:
        ans += base
        continue
    if l == 0:
        base *= nCr(need+u-1,need,mod)
    else:
        base *= nCr(need+u-1,need,mod)*nCr(left//2+d-1,d-1,mod)%mod
    base %= mod
    ans += base
    ans %= mod
print(ans)