Powers of words

Let $t$ be a string and $k$ be a natural number. We define $t^k$ as the result of concatening $t$ exactly $k$ times. For instance, the third power of “abbc” is “abbcabbcabbc”.

Given a string $s$ , rearrange its letters so that the result is the $k$ -th power of some string $t$ , where $k \ge 2$ .

Input

Input consists of several strings, each with between 2 and $10^5$ lowercase letters.

Output

For each given string, print a way to rearrange its letters so that the result is $t^k$ , for some string $t$ and some $k \ge 2$ . If there is more than one solution, choose the alphabetically largest. If there is no solution, print “NO”.

Problem information

Author: Salvador Roura

Generation: 2026-01-25T12:00:15.974Z