Problem:
Score : 100 points

Problem Statement

Given an integer N not less than 3, find the sum of the interior angles of a regular polygon with N sides.

Print the answer in degrees, but do not print units.

Constraints

3 \leq N \leq 100

Input

Input is given from Standard Input in the following format:

N

Output

Print an integer representing the sum of the interior angles of a regular polygon with N sides.

Sample Input 1

3

Sample Output 1

180

The sum of the interior angles of a regular triangle is 180 degrees.

Sample Input 2

100

Sample Output 2

17640

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


#include <iostream>
#include <string>
#include <algorithm>
#include <set>
#include <cmath>
#include <vector>

typedef long long ll;

using namespace std;

int main()
{
    ll n;
    cin >>n;
    cout << 180 * (n - 2) << endl;
    return 0;
}