After calling the function mystery$($x$),$ the output is $43211234.$ What is the value of $x$ in the function call?

void mystery $($int $x)$

$\{$

cout $<mtext\; id="EditorElement\_116343"></mtext><mi\; id="EditorElement\_116344">(</mi>$x$\%10)$;

if $)($

$\{$

$\}$

mystery$($x$/10)$;

cout $(x\%10)$;

$\}$

$4$

$1234$

$4321$

$12344321$