题解 | #单词倒排#

str=input()

#print(str)
str1=[]

a=[]
for i in range(26):
    a.append(chr(ord('a')+i))

    a.append(chr(ord('A')+i))
b=[]
#print(a)
for k in str:
    if k not in a:
    
     b.append(k)
#print(b)

    
for  l in b:
    str=str.replace(l,' ')
#print(str)
c=[]
for   m in str.split(' '):
    c.append(m)
#print(c)
c.reverse()
#print(c)
e=[]
for q in c:
    if q=='':
        continue
    e.append(q)
#print(e)        
d=''
for p in e:
    d+=p+' '
print(d)