# import pypyjit
# pypyjit.set_param('max_unroll_recursion=-1')
from collections import *
from functools import *
from itertools import *
from heapq import *
import sys
input = sys.stdin.readline
mod = 998244353

L,R = map(int,input().split())
A,B,C = map(int,input().split())

M = max(A+B,C)
D = R-L
if D<M:
    print(0)
    exit()
ans = 0
E = D-A-B+1
ans += E*(D-M+1)
ans += (D-A-B)*(D-M+1)*(D-M)//2
ans -= (D-M)*(D-M+1)*(2*D-2*M+1)//6
print(ans%mod)