SWEA 2025 N줄덧셈

import java.util.Scanner;
class Solution {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        int num = sc.nextInt();
        int sum = 0;
        for( int i=1; i<=num; i++ ) sum += i;
        System.out.println(sum);
    }
}