import java.util.*;
public class SumOfNumbers
{
    public static void main(String[]args){
    Scanner input=new Scanner(System.in);
    System.out.print("Enter value of n: ");
    int n=input.nextInt();
    long sum=0;
    for(int i=1;i<=n;i++){
        sum+=i;
    }
    System.out.println("Sum of Numbers from 1 to "+n+" : "+sum);
 }
}