import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################
l,r = na()
mod = 998244353
a,b,c = na()
z = max(a+b,c)
f = a+b
if z > r-l:
    print(0)
else:
    print(-(l-r+z-2)*(l-r+z-1)*(3*f+l-r-2*z-3)//6%mod)