s=raw_input()
l,r=divmod(len(s),4)
if r:l+=1;s+=" "*(r-2)
for i in range(l+1):
 if not i:print s[:l+1]
 elif i<l:print s[-i]+" "*(l-1)+s[l+i]
 else:print s[3*l:2*l-1:-1]