/*
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 * and open the template in the editor.
 */

package graph;

/**
 *
 * @author suchenek
 */
public class STACK {



    private int count;
    private int capacity;
    private int capacityIncrement;
    private int[] itemArray;

    /** Creates a new instance of PriorityQueue */
    public STACK() {
        count=0;
        capacity=10;
        capacityIncrement=2;
        itemArray=new int[capacity];
    }

    public void push(int newItem)
    {
        if(count==capacity) //no more space, "resize" the array up
        {
            capacity*=capacityIncrement;
            int[] tempArray = new int[capacity];
            for (int i = 0; i < count; i++)
            {
                tempArray[i] = itemArray[i];
            }
            itemArray = tempArray;

    }
        itemArray[count++] = newItem;
    }

    public int pop()
    {
        int itemToReturn;
     if (count==0) return -99999;
     itemToReturn=itemArray[--count];


        if ((count < capacity / capacityIncrement) &&  (10 <= capacity / capacityIncrement)) //space wasted, "resize" the array down
        {
          capacity/=capacityIncrement;
            int[] tempArray = new int[capacity];
            for (int i = 0; i < count; i++)
            {
                tempArray[i] = itemArray[i];
            }
            itemArray = tempArray;
        }

        return itemToReturn;
        }
      public int size()
      {
          return count;

      }

      public boolean isEmpty()
      {
          return count==0;
      }
            public int Length()
      {
          return itemArray.length;

      }
    }