import java.util.Scanner;

public class Demo6
{
    public static void main(String[] argv)
    {
	Scanner in = new Scanner(System.in);

	System.out.print("Enter n = ");
	int n = in.nextInt();

        int c = 0;

	int sum = 0;
        for ( int i = 1; i < n; i++ )
           for ( int j = 0; j <= i; j++ )
           {
	       sum = sum + 1;
	       c++ ;              // Count # times we exec the loop
           }

	System.out.println("# time loop executed = " + c);
	System.out.println("n*(n+1)/2 = " + n*(n+1)/2);
    }
}