Java

Define class Stack. Data Member : size, top, array of stack. Member method : push, pop, display. Demonstrate the stack class using main method.

import java.util.*;

class Stack {

int size = 10;

int stack[] = new int[size];

int top = -1;

void push(int element) {

if(top >= size-1) {

System.out.println("Stack is overflow.");

}

else {

top++;

stack[top] = element;

}

}

int pop() {

if(top == -1) {

System.out.println("Stack is underflow.");

return -1;

}

else {

top--;

return stack[top+1];

}

}

void display() {

if(top == -1) {

System.out.println("Stack is underflow.");

}

else {

System.out.println(" ----- Elements in stack ----- ");

System.out.println();

for(int i = top; i >= 0; i--) {

System.out.println(" Elements : " + (top-i+1) + " -> " + stack[i]);

}

}

}

}

class StackDemo {

public static void main(String args[]) {

Stack stack = new Stack();

Scanner sc = new Scanner(System.in);

int choice;

System.out.println(" - - - Operation On Stack - - - ");

do {

System.out.println(" 1. Push\n 2. Pop\n 3. Display\n 4. Exit");

System.out.print("Enter your choice : ");

choice = sc.nextInt();

switch(choice) {

case 1:

System.out.print("Enter element in stack : ");

int element = sc.nextInt();

stack.push(element);

break;

case 2:

System.out.println("Popped element is : " + stack.pop());

break;

case 3:

stack.display();

break;

case 4:

break;

default :

System.out.println("Please enter valid choice.");

break;

}

System.out.println();

}while(choice != 4);

}

}

Output :