def rt(N):
    if 1<=N<=295:
        return 'C++'
    elif 296<=N<=416:
        return 'Rust'
    elif 417<=N<=420:
        return 'Python'

L, R = map(int, input().split())
P =[]
for i in range(L, R+1): 
    P.append(rt(i))

sP = set(P)
print(len(sP)-1)