l,r = map(int, input().split())

cnt = 0

if l <= 295:
	lang = "c"
elif l <= 416:
	lang = "r"
else:
	lang = "p"

for i in range(l, r+1):
	if i <= 295:
		nl = "c"
	elif i <= 416:
		nl = "r"
	else:
		nl = "p"
	if lang != nl:
		cnt += 1
	
	lang = nl

print(cnt)