Coprimes
For given integer N (1<=N<=104) find amount of positive numbers not greater than N that coprime with N. Let us call two positive integers (say, A and B, for example) coprime if (and only if) their greatest common divisor is 1. (i.e. A and B are coprime iff gcd(A,B) = 1).
Input
Input file contains integer N.（ 注意：程序以文件结束符“EOF”结束输入。）
Output
Write answer in output file. 每个数字占一行。
Sample Input
9
Sample Output
6