bash-pure, 69 bytes

Result

WA

Code [DL]

while read -n1 C;{++a[C]};for((;i++<10)){for((j=a[i];j--)){o+=$i}};$o

stdin

7170221427225350484520266444483977528027754563267968220353854644349899648450094575014713136388282293

stdout

stderr

/bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
/code.bash: line 1: syntax error near unexpected token `{for'
/code.bash: line 1: `while read -n1 C;{++a[C]};for((;i++<10)){for((j=a[i];j--)){o+=$i}};$o'

strace