题解 | #学英语#

# 20240918
num1 = ['zero','one','two','three','four','five','six','seven','eight','nine','ten','eleven','twelve','thirteen','fourteen','fifteen','sixteen','seventeen','eighteen','nineteen']
num2 = [0,0,'twenty','thirty','forty','fifty','sixty','seventy','eighty','ninety']
def f100(n):
    if n > 0:
        if n < 20:
            word.append(num1[n])
        else:
            word.append(num2[n//10])
            if n%10 != 0:
                word.append(num1[n%10])

def f1000(n):
    if n >= 100:
        word.append(num1[n//100])
        word.append('hundred')
        if n%100 != 0:
            word.append('and')
    f100(n%100)

while True:
    try:
        n = int(input())
    except:
        break
    else:
        word = []
        a = n%1000
        b = (n//1000)%1000
        c = (n//1000000)%1000
        d = (n//1000000000)%1000
        if d > 0:
            f1000(d)
            word.append('billion')
        if c > 0:
            f1000(c)
            word.append('million')
        if b > 0:
            f1000(b)
            word.append('thousand')
        if a > 0:
            f1000(a)
        print(*word)