list1 = []
n = 30000
for i in range(1,n+1):
    if '7' in list(str(i)):
        list1.append(i)
    if i%7 == 0 and i not in list1:
        list1.append(i)
list1 = sorted(list1)
import bisect
while 1:
    try:
        a = int(input())
        print(bisect.bisect(list1,a))
    except:
        break