1068. Sum

import java.util.Scanner;

public class Main
{
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.println(getSum(Integer.parseInt(scanner.nextLine())));

    }

    public static int getSum(int number) {
        int sum = 0;

        if (number < 1) {
            for (int i = number; i <= 1; i++) {
                sum += i;
            }
            return sum;
        } else if (number > 1) {
            for (int i = 1; i <= number; i++) {
                sum += i;
            }
            return sum;
        }

        return 1;
    }
}