一个任意数制转换的代码

思路是所有原始数制转换成十进制，然后从十进制转换成目标进制：

def fun_any_to_d(n, b): # any to decimal(n : number system, b : operand)
    a = str(b)
    list = []
    for i in a:
        list.append(hex_switch.get(i, "False"))
    for x in list:
        if x not in range(n) :
            return "invalid number"
    sum = 0
    for i in list: 
    	sum = sum * n + int(i)
    return sum


def fun_d_to_any(n, b): # decimal to any
    a = str(b)
    mod = int(a) % n
    var = int(a) // n
    bir = str(mod)
    while var != 0:
        mod = var % n
        bir = str(mod) + bir
        var = var // n
    int_bir = int(bir)
    return int_bir


def fun_any_to_any(origin, expection, oper):# any to any
    temp = fun_any_to_d(origin, oper)
    if temp != "invalid number":
        return fun_d_to_any(expection, temp)
    if temp  == "invalid number":
        return temp        


def fun_sysconvert():  # sys convert
    while True:
        origin = int(input("please enter the original number system(2,8,10,16):"))
        expection = int(input("please enter the number system you want to get(2,8,10,16):"))
        oper = input("please enter the number to convert:")
        print("the result is:")
        print(fun_any_to_any(origin, expection, oper))


hex_switch = {
      # hex switch 十六进制数查表
    '0':0,
    '1':1,
    '2':2,
    '3':3,
    '4':4,
    '5':5,
    '6':6,
    '7':7,
    '8':8,
    '9':9,
    'A':10,
    'B':11,
    'C':12,
    'D':13,
    'E':14,
    'F':15,
    'a':10,
    'b':11,
    'c':12,
    'd':13,
    'e':14,
    'f':15,}


fun_sysconvert() # mian fun