【Python CheckiO 题解】Roman Numerals

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Title Description

[Roman Numerals] : Converts Arabic numerals to Roman numerals

【链接】：https://py.checkio.org/mission/roman-numerals/

[Enter] : An integer form of Arabic numerals

[Output] : a string of Roman numerals

[Premise] : 0 <number <4000

[Example] :

checkio(6) == 'VI'
checkio(76) == 'LXXVI'
checkio(13) == 'XIII'
checkio(44) == 'XLIV'
checkio(3999) == 'MMMCMXCIX'

Problem-solving ideas

First one to ten, ten and one hundred integer integer be listed in tabular form, divided into four cases: a single digit, double-digit, three-digit and four-digit, but also to determine in each case whether or not an integer , it is not an integer, and dividing it by the number of bits of the remainder, again passed to checkio()the function, find the rest of the value.

This method is cumbersome, simple syntax, not suitable for bigger numbers, too dishes, take a look at the god's answer it

Code

def checkio(data):
    roman_list1 = ['I', 'II', 'III', 'IV', 'V', 'VI', 'VII', 'VIII', 'IX']
    roman_list2 = ['X', 'XX', 'XXX', 'XL', 'L', 'LX', 'LXX', 'LXXX', 'XC']
    roman_list3 = ['C', 'CC', 'CCC', 'CD', 'D', 'DC', 'DCC', 'DCCC', 'CM']
    if 0 < data < 10:
        roman = roman_list1[data - 1]
        return roman
    elif 10 <= data < 100:
        if data % 10 == 0:
            roman = roman_list2[data // 10 - 1]
        else:
            roman = roman_list2[data // 10 - 1] + checkio(data % 10)
        return roman
    elif 100 <= data < 1000:
        if data % 100 == 0:
            roman = roman_list3[data // 100 - 1]
        else:
            roman = roman_list3[data // 100 - 1] + checkio(data % 100)
        return roman
    elif 1000 <= data < 9999:
        if data % 1000 == 0:
            roman = 'M' * (data // 1000)
        else:
            roman = 'M' * (data // 1000) + checkio(data % 1000)
        return roman


if __name__ == '__main__':
    # These "asserts" using only for self-checking and not necessary for auto-testing
    assert checkio(6) == 'VI', '6'
    assert checkio(76) == 'LXXVI', '76'
    assert checkio(499) == 'CDXCIX', '499'
    assert checkio(3888) == 'MMMDCCCLXXXVIII', '3888'
    print('Done! Go Check!')

Okami answer

Okami answer NO.1

def checkio(n):
    result = ''
    for arabic, roman in zip((1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1),
                             'M     CM   D    CD   C    XC  L   XL  X   IX V  IV I'.split()):
        result += n // arabic * roman
        n %= arabic
    return result

Okami answer NO.2

roman1 = ('', 'M', 'MM', 'MMM')
roman2 = ('', 'C', 'CC', 'CCC', 'CD', 'D', 'DC', 'DCC', 'DCCC', 'CM')
roman3 = ('', 'X', 'XX', 'XXX', 'XL', 'L', 'LX', 'LXX', 'LXXX', 'XC')
roman4 = ('', 'I', 'II', 'III', 'IV', 'V', 'VI', 'VII', 'VIII', 'IX')

def checkio(data):
    data1 = int(data / 1000)
    data2 = int(data % 1000 / 100)
    data3 = int(data % 100 / 10)
    data4 = int(data % 10 )
    return roman1[data1] + roman2[data2] + roman3[data3] + roman4[data4]

Okami answer NO.3

def checkio(data):
   
    s = ''
    ones = ['X','I', 'II', 'III', 'IV', 'V', 'VI', 'VII', 'VIII', 'IX']
    tens = ['C', 'X', 'XX', 'XXX', 'XL', 'L', 'LX', 'LXX', 'LXXX', 'XC']
    mils = ['M', 'C', 'CC', 'CCC', 'CD', 'D', 'DC', 'DCC', 'DCCC', 'CM']
   
    if data / 1000 != 0:
        s = s + 'M'*(data/1000)
        data = data % 1000
    if data / 100 != 0:
        s = s + mils[data/100]
        data = data % 100
    if data / 10 != 0:
        s = s + tens[data/10]
        data = data % 10
    if data / 1 != 0:
        s = s + ones[data/1]
    return s

Okami answer NO.4

from enum import Enum

class Roman(Enum):
    M  = 1000
    CM = 900
    D  = 500
    CD = 400
    C  = 100
    XC = 90
    L  = 50
    XL = 40
    X  = 10
    IX = 9
    V  = 5
    IV = 4
    I  = 1

    @classmethod
    def encode(cls, n):
        for numeral in cls:
            rep, n = divmod(n, numeral.value)
            yield numeral.name * rep

checkio = lambda n: ''.join(Roman.encode(n))

Okami answer NO.5

def checkio(data):
    base = "I"*data
    
    base = base.replace("I"*5, "V")
    base = base.replace("V"*2, "X")
    base = base.replace("X"*5, "L")
    base = base.replace("L"*2, "C")
    base = base.replace("C"*5, "D")
    base = base.replace("D"*2, "M")
    
    base = base.replace("DCCCC", "CM")
    base = base.replace("CCCC", "CD")
    base = base.replace("LXXXX", "XC")
    base = base.replace("XXXX", "XL")
    base = base.replace("VIIII", "IX")
    base = base.replace("IIII", "IV")
    
    return base