class Node:
    def __init__(self, data):
        self.data = data
        self.next = None
 
class Stack:
    def __init__(self):
        self.top = None
 
    def push(self, data):
        new_node = Node(data)
        new_node.next = self.top
        self.top = new_node
        print("Node is Inserted")
 
    def pop(self):
        if self.is_empty():
            print("EMPTY STACK")
            return
        popped_element = self.top.data
        self.top = self.top.next
        print("Popped Element:", popped_element)
 
    def display(self):
        if self.is_empty():
            print("EMPTY STACK")
            return
        cur = self.top
        stack_elements = []
        while cur:
            stack_elements.append(cur.data)
            cur = cur.next
        print("The stack is:", ' '.join(map(str, stack_elements)))
 
    def is_empty(self):
        return self.top is None
 
stack = Stack()
 
while True:
    try:
        choice = int(input().strip())
        if choice == 1:
            element = input().strip()
            stack.push(element)
        elif choice == 2:
            stack.pop()
        elif choice == 3:
            stack.display()
        elif choice == 4:
            break
        else:
            print("Wrong choice")
    except ValueError:
        print("Wrong choice")
 

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