Problem:
Score : 100 points

Problem Statement

Given is an integer r.

How many times is the area of a circle of radius r larger than the area of a circle of radius 1?

It can be proved that the answer is always an integer under the constraints given.

Constraints

1 \leq r \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

r

Output

Print the area of a circle of radius r, divided by the area of a circle of radius 1, as an integer.

Sample Input 1

2

Sample Output 1

4

The area of a circle of radius 2 is 4 times larger than the area of a circle of radius 1.

Note that output must be an integer - for example, 4.0 will not be accepted.

Sample Input 2

100

Sample Output 2

10000

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

# include <bits/stdc++.h>
//# pragma GCC optimize("Ofast")
# define pb push_back
# define ll long long
# define fi first
# define se second
# define all(vc) vc.begin(),vc.end()
# define forn(i, n) for (int i = 0; i < int(n); i++)
# define ford(i, n) for (int i = int(n) - 1; i >= 0; i--)
# define fore(i, l, r) for (int i = int(l); i < int(r); i++)
# define in freopen("out.txt", "r", stdout)
# define speed ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
# define time cerr << "\nTime elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n"
 
using namespace std;
 
const ll INF = 1e18;
const int mod = 1e9 + 7;
const ll N = 2e6 + 7;
typedef vector < vector < ll > > matrix;

int main()
{   
    speed;
    int n;
    cin >> n;
    cout << n * n;
    time;
}