IntStack.java

public class IntStack {

	private final int[] stack;
	private int top;

	public IntStack() {
		this.top = 0;
		this.stack = new int[5];
	}

	public IntStack(int size) {
		this.top = 0;
		this.stack = new int[size];
	}

	public void push(int element) throws Exception {
		if (top > this.stack.length) {
			throw new Exception("Full stack");
		}
		this.stack[this.top++] = element;
	}

	public int pop() throws Exception {
		if (top <= 0) {
			throw new Exception("Empty stack");
		}
		return this.stack[this.top-- - 1];
	}

}