Method pop

stacks_queues/stack/stack.py:16–21

(self)

        self.top = Node(data, self.top)

    def pop(self):
        if self.top is None:
            return None
        data = self.top.data
        self.top = self.top.next
        return data

    def peek(self):
        return self.top.data if self.top is not None else None