题解 | #挑7#

import re

# 输入数值转换为int
a = int(input())
pattern = r"7"
b = []
# 循环
for i in range(1, a + 1):
    # 判断是否可以被7整除
    if i % 7 == 0:
        b.append(i)
    elif str(i).count("7") > 0:
        b.append(i)
print(len(b))