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Problem G
Inverse Factorial

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A factorial n! of a positive integer n is defined as the product of all positive integers smaller than or equal to n. For example,

21!=12321=51090942171709440000.

It is straightforward to calculate the factorial of a small integer, and you have probably done it many times before. In this problem, however, your task is reversed. You are given the value of n! and you have to find the value of n.

Input

The input contains the factorial n! of a positive integer n. The number of digits of n! is at most 106.

Output

Output the value of n.

Sample Input 1 Sample Output 1
120
5
Sample Input 2 Sample Output 2
51090942171709440000
21
Sample Input 3 Sample Output 3
10888869450418352160768000000
27
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