eolymp
Competitions

Data structures contest - high level

Unexpressed

One integer n is given. How many integers between 1 and n (inclusive) are unrepresentable as ab, where a and b are integers not less than 2?

Input

One positive integer n (n1010).

Output

Print the amount of unrepresentable numbers.

Time limit 1 second
Memory limit 128 MiB
Input example #1
8
Output example #1
6
Input example #2
100000
Output example #2
99634