Archimedes's Problem
Limits: 2 sec., 256 MiB
You are given an integer \(n\).
Find the area of regular polygon with \(n\) vertices and circumradius 1.
Input
The first line contains one integer \(n\).
Output
Print a real number – the area of the polygon.
Your answer will be considered correct if its absolute or relative error does not exceed \(10^{-7}\).
Constraints
\(3 \le n \le 10^{10^5}\).
Samples
| Input (stdin) | Output (stdout) |
|---|---|
| 4 | 2 |
| Element Type | Created | Who | Problem | Compiler | Result | Time (sec.) | Memory (MiB) | # | Actions |
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