Egor has a very old phone. Slava sent Yegor a passphrase from Seryozha's bank account to rob him, but Yegor's phone is so old that it cannot receive long messages. He breaks them into several small random lengths, and they come to him in random order.
When Egor received all these messages, he was really upset. He cursed the phone, threw it against the wall. Unfortunately, the phone turned out to be touchy and mixed all the letters in each message, although it glued all the messages into one. Egor knew that Seryozha loves such lines that all letters in them go in descending order (in reverse alphabetical order). Help Yegor and Slava and find the passphrase from Serezha's bank account using the only remaining message on the phone.
Input
A single line of input contains the string s — message on Egor's phone (1 ≤ |s| ≤ 105). It is guaranteed that s contains only small latin letters.
Imprint
Print a passphrase from Serezha's bank account.
Examples
input
qwerty
output
ywtrqe
input
onehundredseventynine
output
yvutsronnnniheeeeedd