[SWEA] N줄 덧셈

https://swexpertacademy.com/main/code/problem/problemDetail.do?problemLevel=1&contestProbId=AV5QFZtaAscDFAUq&categoryId=AV5QFZtaAscDFAUq&categoryType=CODE&problemTitle=&orderBy=FIRST_REG_DATETIME&selectCodeLang=ALL&select-1=1&pageSize=10&pageIndex=2

SW Expert Academy

 

import java.util.Scanner;
import java.io.FileInputStream;
class Solution
{
	public static void main(String args[]) throws Exception
	{
	
		Scanner sc = new Scanner(System.in);
		int T;
		T=sc.nextInt();
        int score = 0;
		for (int i=0; i<=T; i++){
            score = score + i;
        }
        System.out.print(score);
	}
}

 

N(N+1)/2 가 훨씬 짧고 쉽다