Problem Statement

You are given a string $S$. Find the lexicographically smallest string $S'$ obtained by permuting the characters of $S$.

Here, for different two strings $s = s_1 s_2 \\ldots s_n$ and $t = t_1 t_2 \\ldots t_m$, $s \\lt t$ holds lexicographically when one of the conditions below is satisfied.

• There is an integer $i\\ (1 \\leq i \\leq \\min(n,m))$ such that $s_i \\lt t_i$ and $s_j=t_j$ for all integers $j\\ (1 \\leq j \\lt i)$.
• $s_i = t_i$ for all integers $i\\ (1 \\leq i \\leq \\min(n,m))$, and $n \\lt m$.

Constraints

• $S$ is a string of length between $1$ and $2 \\times 10^5$ (inclusive) consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

$S$

Output

Print the lexicographically smallest string $S'$ obtained by permuting the characters in $S$.

Sample Input 1

aba

Sample Output 1

aab

Three strings can be obtained by permuting aba:

• aba
• aab
• baa

The lexicographically smallest among them is aab.

Sample Input 2

zzzz

Sample Output 2

zzzz