Online-Academy

import java.util.*;
class dynamicStack{
	public static void main(String args[]){
		node temp, top=null;
		System.out.print("Creating Dynamic Stack!!!");
		int choice;
		String str; 
		Scanner sc = new Scanner(System.in);
		
		while(true){
			System.out.print("\n1.Push\n2.Pop\n3.Show\nChoice:");
			choice = sc.nextInt();
			switch(choice){
				case 1:
				System.out.println("Enter Data:");
						str = sc.nextLine();
					    str = sc.nextLine();
						temp = new node();
						temp.data = str;
						temp.address = null; 
						if(top == null){
							top = temp;
						}else{
							temp.address = top;
							top = temp;
						}
				break;
				case 2: System.out.println("Popping Stack!!!");
						System.out.println("Top of Stack : "+top.data);
							temp = top.address;
							top = temp;
							temp = null; 
				break;
				case 3: System.out.println("Show contents of Stack: \n");
						if(top != null){
						for(temp=top;temp.address!=null;temp=temp.address){
							System.out.print(temp.data+"  ");
						}
							System.out.print(temp.data+"  ");
						}
				break;
				default: System.exit(0);
				break; 
			}
		}
	}
}

Output:
Creating Dynamic Stack!!!
1.Push
2.Pop
3.Show
Choice:1
Enter Data:
apple

1.Push
2.Pop
3.Show
Choice:1
Enter Data:
mango

1.Push
2.Pop
3.Show
Choice:3
Show contents of Stack:

mango  apple
1.Push
2.Pop
3.Show
Choice:2
Popping Stack!!!
Top of Stack : mango

1.Push
2.Pop
3.Show
Choice: