import java.util.EmptyStackException;


public class stack_array<T> implements stack{

	private T[] stack;
	private int lastPos = 0;

	private stack_array(int length){
		stack = (T[]) new Object[length];
	}

	public <T> T pop( T[] a) throws EmptyStackException {
		if (this.lastPos < 0){
			throw new EmptyStackException();
		}
		else
		{
		this.lastPos --;
		return (T) stack[lastPos];
		}
	}

	@SuppressWarnings("hiding")
	public void insert(T a){
		if (this.lastPos >= stack.length){
			throw new ArrayIndexOutOfBoundsException();
		}
		else
		{
		this.lastPos ++;
		stack[lastPos] = a;
		}
	}
}