public class OurArrayList {

	private int numElements;
	
	private int[] numbers;


	public OurArrayList() {

		numElements = 0;

		numbers = new int[10];
	}

	public int size() {

		return numElements;

	}

	public int get(int index) throws Exception {
		
		if(index<0 || index>=size())
			throw new IndexOutOfBoundsException();
		return numbers[index];
	}


	public int set(int index, int value)
				throws Exception {


		int old = get(index);
		numbers[index] = value;
		return old;


	}


	public void add(int value) {

		if(numElements==numbers.length)
			grow();

		numbers[numElements] = value;
		numElements++;

	}


	private void grow() {

		int[] temp = new int[numElements*2];

		for(int i=0; i<numbers.length; i++)
		     temp[i] = numbers[i];

		numbers = temp;

	}








}