// Pretty-much complete ArrayIntList class
// NOTE: FOR HOMEWORK 1, DON'T USE THIS FILE AS YOUR STARTING POINT.
//       USE THE ArrayIntList.java LINK FROM THE "Homework" PAGE.
public class ArrayIntList {
    // class constant for default list capacity
    public static final int DEFAULT_CAPACITY = 10;

	// encapsulated -- clients can't break them
    private int[] elementData;
	private int size;
    
    // constructor 1: initializes a new list that stores up to 10 elements.
    public ArrayIntList() {
        // calls the (int capacity) constructor
        this(DEFAULT_CAPACITY);
    }
    
    // constructor 2: initializes a new list that stores up to the
    // given number of elements.
    // pre: capacity > 0
    public ArrayIntList(int capacity) {
        elementData = new int[capacity];
        size = 0;
    }

    // accessor - a method that gives the client information about the object.
    // post: returns the number of elements in the list.
    public int size() {
        return size;
    }

    // pre: 0 <= index <= size-1
    // post: returns the element at the given index.
    public int get(int index) {
        return elementData[index];
    }

    // pre: size < elementData.length - 1  (there is room in the array)
	// post: adds an integer to the end of this list.
	public void add(int value) {
		elementData[size] = value;
		size++;
	}

    // pre: size < elementData.length - 1  (there is room in the array)
    // pre: 0 <= index <= size
	// post: inserts an integer to this list at the specified index.
	public void add(int index, int value) {
		for (int i = size - 1; i >= index; i--) {
			elementData[i+1] = elementData[i];
		}
	
		elementData[index] = value;
		size++;
	}
    
    // pre: 0 <= index <= size-1
    // post: removes the value at the given index, shifting subsequent values left.
    public void remove(int index) {
        // shift elements to the left (cover the gap)
        for (int i = index + 1; i <= size - 1; i++) {
            elementData[i-1] = elementData[i];
        }
        elementData[size - 1] = 0;
        
        // reduce the size
        size--;
    }

	// returns a String representation of the list in human-readable form.
	public String toString() {
		if (size == 0) {
			return "[]";
		} else {
			String result = "[" + elementData[0];
			for (int i = 1; i < size; i++) {
				result += ", " + elementData[i];
			}
			result += "]";
			return result;
		}
	}
}