php, 52 bytes

Result

WA

Code [DL]

<?php $a=readline().str_split();sort($a);echo ""+$a;

stdin

2112981495275140640369752892657695987713693224367680414200036101868657668323036748446845506195252322

stdout

2.1129814952751E+99

stderr

PHP Warning:  str_split() expects at least 1 parameter, 0 given in /volume/CODE on line 1
PHP Warning:  sort() expects parameter 1 to be array, string given in /volume/CODE on line 1

strace