如何在python中将NoneType转换为int？

我想尝试使用Python中的堆栈将十进制数转换为二进制数,但是我得到了这个错误.

class Stack:
    def __init__(self):
        self.items = []

    def is_empty(self):
        return self.items == []

    def push(self, item):
        self.items.append(item)

    def pop(self):
        self.items.pop()

    def peek(self):
        return self.items[len(self.items)-1]

    def size(self):
        return len(self.items)



def divideBy2(decNumber):
    remstack = Stack()

    while decNumber > 0:
        rem = decNumber % 2
        remstack.push(rem)
        decNumber = decNumber // 2

    binString = ""
    while not remstack.is_empty():
        binString = binString + str(remstack.pop())

    return binString

print(divideBy2(42))

Daniel.. 5

你的pop方法遗漏了return.

你的pop方法遗漏了return.