/*
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 * and open the template in the editor.
 */
package stack1325;

/**
 *
 * @author jcmt
 * Stack1325 mystack = new Stack1325();
 * Stack1325 mystack2 = new Stack1325(200);
 */
public class Stack1325 {
    
    private int[] intStack;
    private int topOfStack; //top of stack starts at 10
    private int botOfStack; //bottom of empty stack is 10
    private int numOfStEl;  //number of elephants in the stack
    private int maxStEl;
    
    // in the constructor set initial values for top, bot, etc.
    
    public Stack1325()
    {
        intStack = new int[10];
        topOfStack = 10;
        botOfStack = 10;
        maxStEl = 10;
    }
    
    public Stack1325(int size)
    {
        if (size <0)
            size = 10;
        intStack = new int[size];
        topOfStack = size;
        botOfStack = size;
        maxStEl = size;
    }
    
    
    
    // push, pop, isEmpty, isFull, numberOfEle, 
    
    public boolean isEmptyStk()
    {
        boolean flag = false;
        if (numOfStEl == 0)
        {
            flag = true;
        }
        return flag;
    }
    
    public boolean isFullStk()
    {
        boolean flag = false;
        
        if (topOfStack == 0)
        {
         flag = true;
         
        }
        
        return flag;
    }
    
    public boolean push(int newTop)
    {
        boolean flag = true;
        if (isFullStk() ||  (!(isValid(newTop))))
        {
            flag = false;
        }
        else
        {
            if (isEmptyStk())
            {
                botOfStack--;
                }
            topOfStack--;
        
            intStack[topOfStack] = newTop;
            numOfStEl++;
            
        }
        
        return flag;  // return true;
    }

    private boolean isValid(int input)
    {
        boolean flag = true;
        if (input < 0)  //inputs must be 0 or positive
            flag = false;
        return flag;
        
        //return (input >= 0);
        
    }
    
    
    public int pop()
    {
        if (isEmptyStk())
            return -1; //Assume the values in stack must be pos
        numOfStEl--;
        topOfStack++;
        if (isEmptyStk())
            botOfStack = maxStEl;
        return intStack[topOfStack-1];
        
    }
    

    public void stkInspector()
    {
        if (isEmptyStk())
        {
            System.out.println("The stack is empty.");
            
        }
        else 
        {
            for (int i=topOfStack; i < maxStEl; i++)
            {
                System.out.println(intStack[i]);
           
            }
        }
    }
    
    
    
}