# convert numbers into different number systems
# iterative version
import sys


def user_input():
    number = int(input('decimal number to convert: '))
    return number

def decimal_to_binary(number):
    # decimal to binary
    decimal_number = ''
    # set div to a number to make the while loop work
    div = 1 
    while (div != 0):
        div = number // 2
        reminder = number % 2
        number = div
        #print(reminder)
        decimal_number += str(reminder)
    return print('binary: ', decimal_number[::-1]) 

def decimal_to_octal(number):
    octal_number = ''
    div = 1
    while (div != 0):
        div = number // 8
        reminder = number % 8
        number = div
        octal_number += str(reminder)
    return print('octal: ', octal_number[::-1])

def decimal_to_duodecimal(number):
    duodecimal_number = ''
    div = 1
    while (div != 0):
        div = number // 12
        reminder = number % 12
        if (reminder > 9):
           reminder = switcher(reminder)
        number = div
        duodecimal_number += str(reminder)
    return print('duodecimal: ', duodecimal_number[::-1]) 
  
def decimal_to_hex(number):
    hex_number = ''
    div = 1
    while (div != 0):
        div = number // 16
        reminder = number % 16
        if (reminder > 9):
           reminder = switcher(reminder)
        number = div
        hex_number += str(reminder)
    return print('hexadezimal: ', hex_number[::-1])

# switcher to select the correct char for hex number lager then 9
def switcher(n):
    switcher = {
            10: 'A',
            11: 'B',
            12: 'C',
            13: 'D',
            14: 'E',
            15: 'F'
            }
    return switcher.get(n)

def main():
    number = user_input()
    decimal_to_binary(number)
    decimal_to_octal(number)
    decimal_to_duodecimal(number)
    decimal_to_hex(number)

if __name__ == "__main__":
    main()