/* 

Computing the sum of n numbers recursively vs. iteratively.

Laura Toma
csci101
*/


public class RecSum {
	
	public static void main (String args[]) {

		int k = 10; 

		//compute the sum of the first k numbers
		int s = sum(k);


		System.out.println("Sum of " + k + " numbers is " + s);
		
	} // end of main
	

	//a recursive method to compute the sum 1 + 2 + .... + k
	public static int sum (int k) {
		if (k > 0)
			return k + sum(k-1);
		else 
			return 0;
	}


	//for comparison, here is  an iterative version of sum
	public static int sumIterative(int k) {
		
		int i, s = 0;
		for (i = 0; i< k; i++) 
			s = s + i;
		return s;
	}

	
} // end of class