Question

Complete the following functions in the Stack.java/Stack.h files (ATTACHED BELOW):
a. void push(int val)
b. int pop()
c. int getSize()

public class Stack {
  
private int maxStackSize, topOfStack;
private int[] stack;
  
public Stack(int maxStackSize) {
if (maxStackSize <= 0)
System.out.println("Stack size should be a positive integer.");
else {
this.maxStackSize = maxStackSize;
topOfStack = -1;
stack = new int[maxStackSize];
}
}
  
public void push(int val) { // complete this function
}
  
public int pop() { // complete this function
}
  
public int getSize() { // complete this function
}
}

Answer 1

public class Stack {

    private int maxStackSize, topOfStack;
    private int[] stack;

    public Stack(int maxStackSize) {
        if (maxStackSize <= 0)
            System.out.println("Stack size should be a positive integer.");
        else {
            this.maxStackSize = maxStackSize;
            topOfStack = -1;
            stack = new int[maxStackSize];
        }
    }

    public void push(int val) { // complete this function
        if (topOfStack >= maxStackSize - 1)
            System.out.println("Stack is already full.");
        else
            stack[++topOfStack] = val;
    }

    public int pop() { // complete this function
        if (topOfStack == -1) {
            System.out.println("Stack is already empty");
            return -1;
        }
        else 
            return stack[topOfStack--];
    }

    public int getSize() { // complete this function
        return topOfStack+1;
    }
}