s=input().strip()
letter=[]
for i , c in enumerate(s):
    if c.isalpha():
        letter.append((i,c))
sort_le=sorted(letter,key=lambda x:(x[1].lower(),x[0]))
result = list(s)
a=0
for i , c in enumerate(s):
    if c.isalpha():
        result[i]=sort_le[a][1]
        a+=1
print(''.join(result))