Sum Related Problem

Description

You are given a number N, find sum of all even numbers which occur before N (inclusive of N if N is even)

Input

Input Format

First and the only line contains one number N.

Constraints

N<10000

Output

Output Format

Output one number which is sum (under above condition)

Sample Input 1 

8

Sample Output 1

20

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int eng= sc.nextInt();
        int sum = 0;
        for(int i =0;i<=eng;i++){
            if(i%2==0){
                sum=sum+i;
            }
        }
        System.out.println(sum);
    }
}