What number will this code output $37,41,32,$ or $18?$

public class Question $\{$

public static int checksum$($String number$)\{$

int total $=0$;

boolean multiply $=$ false;

for $($int i $=0$; i $$ number.length$()$; i$++)\{$

int digit $=$ Integer.parseInt$(""+$ number.charAt$($i$))$;

if $($multiply$)\{$

digit $*=3$;

if $($digit $>10)\{$

digit $-=2$;

$\}$

$\}$

total $+=$ digit;

multiply $=!$multiply;

$\}$

return total;

$\}$

public static void main$($String$[]$ args$)\{$

System.out.println$($checksum$("723481"))$;

$\}$

$\}$