Question

java

create java program that make stack with LinkedList and stack is implement iterator. When stack’s iterator call next(), it pop its data.
here is the example of output
//by user
5
1 2 3 4 5
//then output comes like this
5
4
3
2
1
Stack is empty.

here is the code that i'm going to use

class Stack<T> implements Iterator<T> {
   LinkedList<T> list;
  
   public Stack() {
       list = new LinkedList<T>();
   }
  
   public boolean isEmpty() {
       return list.isEmpty();
   }
  
   public void push(T data) {
       // need code
   }
  
   public T pop() {
       if (list.isEmpty())
           return null;
      
       // need code
   }
       public T peek() {
       if (list.isEmpty())
           return null;
      
       // need code
   }
  
   public boolean hasNext() {
       if (list.size() <= 0)
           return false;
       return true;
   }

   public T next() {
   // need code
   }
}

class Main {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
       Stack<Integer> stack = new Stack<>();
      
       int count = sc.nextInt();
       for (int i = 0; i < count; i++) {
           int num = sc.nextInt();
           stack.push(num);
       }
      
       Iterator<Integer> itr = stack;
       while(itr.hasNext())
           System.out.println(itr.next());
      
       if (stack.isEmpty())
           System.out.println("Stack is empty.");
      
       sc.close();
}
}

Answer 1

//java code

import java.util.Iterator;
import java.util.LinkedList;

class Stack<T> implements Iterator<T> {
    LinkedList<T> list;

    public Stack() {
        list = new LinkedList<T>();

    }

    public boolean isEmpty() {
        return list.isEmpty();
    }

    public void push(T data) {
;
        list.push(data);
    }

    public T pop() {
        if (list.isEmpty())
            return null;

        T data= list.pop();
        return data;
    }
    public T peek() {
        if (list.isEmpty())
            return null;

        // need code
        T data= list.peekFirst();
        return data;
    }

    public boolean hasNext() {
        if (list.size() <= 0)
            return false;
        return true;
    }

    public T next() {
        // need code
        T data= list.pop();

        return data;
    }
}

import java.util.Iterator;
import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Stack<Integer> stack = new Stack<>();
System.out.print("How many numbers you want to stack: ");
        int count = sc.nextInt();
        System.out.println("Enter numbers: ");
        for (int i = 0; i < count; i++) {
            int num = sc.nextInt();
            stack.push(num);
        }
System.out.println("Peek value: "+stack.peek());
        Iterator<Integer> itr = stack;
        while(itr.hasNext())
            System.out.println(itr.next());

        if (stack.isEmpty())
            System.out.println("Stack is empty.");

        sc.close();
    }
}

//output

Enter numbers: Peek value: 5 Stack is empty

//if you need any help regarding this solution ............ please leave a comment ............ thanks..