题解 | #学英语#

n = int(input())
new = ""
k, m, b = False, False, False
if n < 1000000 and n >= 1000:
    k = True
if n < 1000000000 and n >= 1000000:
    m = True
if n >= 1000000000:
    b = True
vocab = {
    "1": "one",
    "2": "two",
    "3": "three",
    "4": "four",
    "5": "five",
    "6": "six",
    "7": "seven",
    "8": "eight",
    "9": "nine",
    "10": "ten",
    "11": "eleven",
    "12": "twelve",
    "13": "thirteen",
    "14": "fourteen",
    "15": "fifteen",
    "16": "sixteen",
    "17": "seventeen",
    "18": "eighteen",
    "19": "nineteen",
}
vocab2 = {
    "2": "twenty",
    "3": "thirty",
    "4": "forty",
    "5": "fifty",
    "6": "sixty",
    "7": "seventy",
    "8": "eighty",
    "9": "ninety",
}


def kd(n, new):
    n = str(n)
    if n == "000":
        return new
    if len(n) == 3:
        new = "".join([new, vocab[n[0]]])
        a = int(n) % 100
        if a == 0:
            new = " ".join([new, "hundred "])
            return new
        new = " ".join([new, "hundred and "])
        if a >= 20:
            a = str(a)
            new = "".join([new, vocab2[a[0]]])
            if a[1] == '0':
                return new
            new = " ".join([new, vocab[a[1]]])
        elif a < 20:
            a = str(a)
            new = "".join([new, vocab[a]])
    elif len(n) < 3:
        if n == "00":
            return new
        if int(n) >= 20:
            new = "".join([new, vocab2[n[0]]])
            if n[1] == '0':
                return new
            new = " ".join([new, vocab[n[1]]])
        elif int(n) < 20:
            new = "".join([new, vocab[n]])
    return new


def md(n, new):
    n = str(n)
    if n == "000":
        return new
    if len(n) == 3:
        new = "".join([new, vocab[n[0]]])
        a = int(n) % 100
        if a == 0:
            new = " ".join([new, "hundred "])
            return "".join([new, ' thousand '])
        new = " ".join([new, "hundred and "])
        if a >= 20:
            a = str(a)
            new = "".join([new, vocab2[a[0]]])
            if a[1] == '0':
                return "".join([new, ' thousand '])
            new = " ".join([new, vocab[a[1]]])
        elif a < 20:
            a = str(a)
            new = "".join([new, vocab[a]])
    elif len(n) < 3:
        if n == "00":
            return "".join([new, ' thousand '])
        if int(n) >= 20:
            new = "".join([new, vocab2[n[0]]])
            if n[1] == '0':
                return "".join([new, ' thousand '])
            new = " ".join([new, vocab[n[1]]])
        elif int(n) < 20:
            new = "".join([new, vocab[n]])
    return "".join([new, ' thousand '])


def bd(n, new):
    n = str(n)
    if n == "000":
        return new
    if len(n) == 3:
        new = "".join([new, vocab[n[0]]])
        a = int(n) % 100
        if a == 0:
            new = " ".join([new, "hundred "])
            return "".join([new, ' million '])
        new = " ".join([new, "hundred and "])
        if a >= 20:
            a = str(a)
            new = "".join([new, vocab2[a[0]]])
            if a[1] == '0':
                return "".join([new, ' million '])
            new = " ".join([new, vocab[a[1]]])
        elif a < 20:
            a = str(a)
            new = "".join([new, vocab[a]])
    elif len(n) < 3:
        if n == "00":
            return "".join([new, ' million '])
        if int(n) >= 20:
            new = "".join([new, vocab2[n[0]]])
            if n[1] == '0':
                return "".join([new, ' million '])
            new = " ".join([new, vocab[n[1]]])
        elif int(n) < 20:
            new = "".join([new, vocab[n]])
    return "".join([new, ' million '])

def bu(n, new):
    n = str(n)
    if n == "000":
        return new
    if len(n) == 3:
        new = "".join([new, vocab[n[0]]])
        a = int(n) % 100
        if a == 0:
            new = " ".join([new, "hundred "])
            return "".join([new, ' billion '])
        new = " ".join([new, "hundred and "])
        if a >= 20:
            a = str(a)
            new = "".join([new, vocab2[a[0]]])
            if a[1] == '0':
                return "".join([new, ' billion '])
            new = " ".join([new, vocab[a[1]]])
        elif a < 20:
            a = str(a)
            new = "".join([new, vocab[a]])
    elif len(n) < 3:
        if n == "00":
            return "".join([new, ' billion '])
        if int(n) >= 20:
            new = "".join([new, vocab2[n[0]]])
            if n[1] == '0':
                return "".join([new, ' billion '])
            new = " ".join([new, vocab[n[1]]])
        elif int(n) < 20:
            new = "".join([new, vocab[n]])
    return "".join([new, ' billion '])

if n < 1000:
    print(kd(n, new))
elif n < 1000000 and n >= 1000:
    n = str(n)
    lenth = len(n)
    new = md(int(n[:lenth-3]), new)
    print(kd(int(n[lenth-3:]), new).strip())
elif n < 1000000000 and n >= 1000000:
    n = str(n)
    lenth = len(n)
    new = bd(int(n[:lenth-6]), new)
    new = md(int(n[lenth-6:lenth-3]), new)
    print(kd(int(n[lenth-3:]), new).strip())
elif n >= 1000000000:
    n = str(n)
    lenth = len(n)
    new = bu(int(n[:lenth-9]), new)
    new = bd(int(n[lenth-9:lenth-6]), new)
    new = md(int(n[lenth-6:lenth-3]), new)
    print(kd(int(n[lenth-3:]), new).strip())