from math import comb
l, r = map(int, input().split())
a, b, c = map(int, input().split())
k = r - l - a - b
d = c - a - b
if k < 0:
    print(0)
    exit()
ans = comb(k + 3, 3)
if d > 0:
    ans -= - d * (d + 1) * (-3 * k + 2 * d - 5) // 6
print(ans % 998244353)