l, r = map(int, input().split())
a = list(range(l, r+1)) + [0]
cnt = 0
for i in range(len(a)):
    if a[i] == 295 and a[i+1] == 296:
        cnt += 1
    if a[i] == 416 and a[i+1] == 417:
        cnt += 1
print(cnt)