[백준/Java] 8393번 :: 합

import java.util.Scanner;

public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		
		int n = sc.nextInt();
		int a = 0;
		
		for (int i = 1; i <= n; i++)
			a += i;
		System.out.print(a);
	}
}