1b.txt

Write a Java program to implement the Stack using arrays. Write Push(), Pop(), and Display() methods to demonstrate its working.


import java.util.*;

class arrayStack
 {
	int arr[];
	int top, max;

	arrayStack( int n)
{
		max = n;
		arr = new int[max];
		top = -1;
	}

	void push( int i )
{
		if (top == max - 1)
			System.out.println("Stack Overflow");
		else
			arr[++top] = i;
	}
	void pop() 
{
		if (top == -1) 
{
			System.out.println("Stack Underflow");
		}
else
 {
			int element = arr[top--];
			System.out.println("Popped Element:  " + element);
		}
	}
	void display() 
{
		System.out.print("\nStack = ");
		if (top == -1) 
{
			System.out.print("Empty\n");
			return;
		}
		for (int i = top; i >= 0; i--)
			System.out.print(arr[i] + " ");
		System.out.println();
	}
}
class Stack
{
	public static void main(String[] args) 
{
		Scanner scan = new Scanner(System.in);
		System.out.println("Enter Size of Integer Stack ");
		int n = scan.nextInt();
		boolean done = false;

		arrayStack stk = new arrayStack(n);

		char ch;
		do 
{
			System.out.println("\nStack Operations");
			System.out.println("1. push");
			System.out.println("2. pop");
			System.out.println("3. display");
			System.out.println("4. Exit");

			int choice = scan.nextInt();
			switch (choice) 
{
				case 1: System.out.println("Enter integer element to push");
				             stk.push(scan.nextInt());
					 break;

				case 2: stk.pop();
					 break;

				case 3: stk.display();
				 	 break;

				case 4: done = true;
					 break;

				default: System.out.println("Wrong Entry \n ");
					  break;
			}

		} while (!done);
	}
}