empty=[]

def make_text(sentence):
  word = sentence[-2]
  empty.append(word)
  for i in range(len(sentence)):
    new_word = (sentence[-i -3])
    empty.append(new_word)

    i = i +1

  return empty


sentence= input()
make_text()

new_sentence = "".join(empty)
final_sentence = sentence + new_sentence

print(final_sentence)