题解 | #学英语#

a=input()
num1=['','one','two','three','four','five','six','seven','eight','nine','ten','eleven','twelve','thirteen','fourteen','fifteen','sixteen','seventeen','eighteen','nineteen']
num2=['','','twenty','thirty','forty','fifty','sixty','seventy','eighty','ninety']
num3=['hundred','thousand','million','billion']
k=[]
n=[]
b=''
a1=list(a)[::-1]
for i in range(len(a1)):
    k+=[a1[i]+b]
    b+='0'

for i in range(len(k)):
    if len(k[i])<=2 and int(k[i])<10 and k[i]!='0' and k[i]!='00' and a[-2]!='1': n+=[num1[int(k[i])]]
    elif k[i]=='10':n+=[num1[int(a[-2:])]]
    elif (int(k[i])>=20 and len(k[i])==2) or (int(k[i][:2])>=20 and len(k[i])==5): n+=[num2[int(k[i][0])]]
    elif (len(k[i])==3 and a[-2:]!='00' and k[i]!='000') or (len(k[i])==6 and k[i]!='000000'): n+=[num1[int(k[i][0])]+' '+num3[0]+' and']
    elif len(k[i])==3 and a[-2:]=='00' and k[i]!='000': n+=[num1[int(k[i][0])]+' '+num3[0]]
    elif len(k[i])==4 and k[i]!='0000': n+=[num1[int(k[i][0])]+' '+num3[1]]
    elif len(k[i])==4 and k[i]=='0000': n+=[num3[1]]
    elif len(k[i])==7: n+=[num1[int(k[i][0])]+' '+num3[2]]

n=n[::-1]
print(' '.join(n))