package lectures;

public class Prac1 {

	public static void main(String[] args) {
		SLList la = new SLList();
		SLList lb = new SLList();

		//la = {5,3,1}
		la.add(1);
		la.add(3);
		la.add(5);

		//lb = {8,7,6,4,2}
		lb.add(2);
		lb.add(4);
		lb.add(6);
		lb.add(7);
		lb.add(8);

		SLList lr = new SLList();
		lr.add(1);
		lr.add(2);
		lr.add(3);
		lr.add(4);
		lr.add(5);
		lr.add(6);

		la.llreverse(); //{1,3,5}
		lb.llreverse(); //{2,4,6,7,8}
		lr.llreverse();


		//list should be {1,2,3,4,5,6,7,8}
		interleaf(la,lb).printAll();

	}

	/**
	 *
	 * @param l1 {1,3,5}
	 * @param l2 {2,4,6,7,8}
	 * @return should be {1,2,3,4,5,6,7,8}
	 */
	public static SLList interleaf(SLList l1, SLList l2) {


		SLList interList = new SLList(); //our final result

		//determines if any of list is empty as each iteration we
		//go through the head is removed
		while(!l1.isEmpty() && !l2.isEmpty()) {

			interList.add(l1.head.info);
			l1.deleteHead();//after add, l1.head.info is removed


			interList.add(l2.head.info);
			l2.deleteHead();//after add, l2.head.info is removed

		}

		/**if lists are uneven in size, we will put the
			remaining larger list in our interList
		*/
		while(!l1.isEmpty()) {
			interList.add(l1.head.info);
			l1.deleteHead();
		}
		while(!l2.isEmpty()) {
			interList.add(l2.head.info);
			l2.deleteHead();
		}

		//right now its backwards, so we need to reverse it
		interList.llreverse();
		return interList;
	}
}