0004. Shar
Time limit : 1000 ms
Memory limit : 64 mb
Radiusi r bo`lgan sharning yuzini toping.
Kiruvchi ma’lumotlar: bitta butun son $r (1\le r \le 100)$
Chiquvchi ma’lumotlar: bitta son masala yechimi. Javobni $10^{-2}$ aniqlikda chiqaring.
| Input |
|---|
| 2 |
| Output |
| 50.27 |
| Input |
|---|
| 17 |
| Output |
| 3631.68 |