# StackModule.py
#!/usr/bin/python3
import copy

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

    def isEmpty(self):
        return len(self.items) == 0

    def push(self, element):
        try:
            self.items.append(element)
            return True
        except Exception as e:
            return False

    def pop(self):
        try:
            return self.items.pop()
        except Exception as e:
            return None

    def peek(self):
        try:
            return self.items[len(self.items)-1]
        except Exception as e:
            return None

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

    def __str__(self):
        output = []

        items = copy.copy(self.items)
        items.reverse()

        for item in items:
            output.append(str(item))

        return " -> ".join(output)
            

#!/usr/bin/python3
from StackModule import Stack

def decimal2binary(d):
    s = Stack()

    while d > 0:
        rem = d%2
        d = d//2
        s.push(rem)

    b = ''
    while s.size() > 0:
        b = b+str(s.pop())

    return b

if __name__ == '__main__':
    print(decimal2binary(9)) # 1001
    print(decimal2binary(233)) # 11101001