Stack

from src.linked_list_node import LinkedListNode


class Node:
    def __init__(self, value):
        self.value = value
        self.next = None


class CustomStack:
    def __init__(self):
        self.head = None
        self.count = 0

    def push(self, value):
        if self.head is not None:
            new_node = Node(value)
            new_node.next = self.head
            self.head = new_node

        else:
            self.head = Node(value)

        self.count += 1

    def pop(self):
        if self.head is not None:
            popped = self.head.value
            self.head = self.head.next
            self.count -= 1
            return popped
        else:
            raise ValueError

    def is_empty(self):
        if self.count == 0:
            return True
        else:
            return False

    def peek(self):
        if self.head is None:
            raise ValueError
        else:
            return self.head.value

    print()


stack = CustomStack()
stack.push(1)
stack.push(2)
# stack.push(3)

print(stack.count)