题解 | #挑7#
挑7
https://www.nowcoder.com/practice/ba241b85371c409ea01ac0aa1a8d957b
n=int(input())
cnt=0
for i in range(1,n+1):
if i%7==0:
#print(i)
cnt += 1
else:
l=list(str(i))
if l.count('7')>0:
cnt += 1
#print(i)
print(cnt)