Let f(x) denote the number of positive integers which are less than x and also co-prime to x i.e. gcd(x, i) = 1 , where 1 ≤ i ≤ x-1. For example f(2) = 1 as only i = 1 satisfies the condition, f(6) = 2 as only i = 1 and i = 5 satisfy the condition.

We also define f(1) = 1

Your task is to compute the following sum:

where **N** is some positive integer.

**Input Format**

The only line in each test case consists of **N** , a positive integer.

**Constraints**

**1 ≤ N ≤ 109**

**Output Format**

Output a single integer - value of the sum

**Sample Input 0**

6

**Sample Output 0**

12

**Explanation 0**

Some of the values are: f(1) = 1 , f(2) = 1, f(3) = 2, f(4) = 2, f(5) = 4, f(6) = 2 Therefore we output (1+1+2+2+4+2) = 12