Neelix has been working on making the Altonian warp bubble power itself up. While waiting for the system checks to complete, he saw a number on his screen and wondered if there is a number that powers itself up to this number.

-----Input-----
The first and only input line consists of a single integer $n$, the number Neelix saw on his screen.

-----Output-----
Output the number $x$, where $x^x = n$. Your answer must have an absolute or relative error of at most $10^{-6}$.

-----Limits-----
- $1 \leq n \leq 10000000000$

-----Examples-----
Sample Input:
4
Sample Output:
2.0

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