bash-pure, 105 bytes

Result

WA

Code [DL]

a=()
while read -n 1 c;do;a+=($c);done
for e in ${a[@]};do for f in ${a[@]}; do echo $e;echo $f;done;done

stdin

6563880727206450437826190252840799503611197892987355912282307409145259817710260545930649760473044609

stdout

stderr

/bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
/code.bash: line 2: syntax error near unexpected token `;'
/code.bash: line 2: `while read -n 1 c;do;a+=($c);done'

strace