public class Summation extends Thread {
	public Summation (int n) {
		upper = n;
	}

	public void run () {
		int sum = 0;
		
		if (upper > 0) {
			for (int i = 1; i <= upper; i++)
				sum += i;
		}

		System.out.println("The sum of "+upper+" is "+sum);
	}
	
	private int upper;
}