Problem C
Approval Area
Languages
en
is
The current policy of the government can be represented by a point in the plane. A voter’s ideal policy would also be represented by a point in the plane. The voter’s unhappiness with the current policy is measured by the distance between these two points. Many different distance metrics may be used, but we will use squared Euclidean distance here.
The voter’s unhappiness with the current policy is $u$. A new policy is proposed and is put to the vote.
The voter’s approval area is the set of points representing policies that the voter would be willing to vote for to replace the current policy. Determine the area of the voter’s approval area.
Input
The first and only line contains one integer $u$, where $0 \leq u \leq 4 \cdot 10^{14}$.
Output
Output the area of the voter’s approval area. Your output is considered correct if it has at most a relative error of $10^{-9}$.
| Sample Input 1 | Sample Output 1 |
|---|---|
0 |
0E-100 |
| Sample Input 2 | Sample Output 2 |
|---|---|
3 |
9.424777960769379715387930149838508652591508198125317462924833776923449218858626995884104476026351204 |
| Sample Input 3 | Sample Output 3 |
|---|---|
400000000000000 |
1256637061435917.295385057353311801153678867759750042328389977836923126562514483599451213930136846827 |
