package com.ds; import java.util.Arrays; public class StackDArray { Object[] ArrayStack; int size; int top; public StackDArray(int size) { this.size=size; ArrayStack= new Object[this.size]; top=-1; } public void push(Object newItem){ ensureCapacity(top+2); top=top+1; ArrayStack[top]=newItem; } public void ensureCapacity( int minCapacity){ int oldCapacity= getSize(); if(minCapacity>oldCapacity){ int newCapacity=oldCapacity*2; if(newCapacity