bash-pure, 204 bytes

Result

WA

Code [DL]

a=()
while read -n 1 c;do a+=($c);done
for((i=0;i<100;i++));do for((j=0;j<99;j++));do k=$((j+1));if [[ a[$j] > a[$k] ]];then t="${a[$k]}";a[$k]="${a[$j]}";a[$j]=$t;fi;done;done
echo $(IFS=;echo "${a[*]}")

stdin

6218991633307667195182819664514706335386340186736949867284138654055055289898743583222593237546321151

stdout

6218991633307667195182819664514706335386340186736949867284138654055055289898743583222593237546321151

stderr

/bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)

strace