$3.(20$ pts$)$ Validating inputs; for example, log is only defined when its argument is positive $(>0).$

a$)$ Please complete the logarithm program code below to validate log input argument $\backslash (>\backslash$mathbf$\{0\}\backslash ).$

$/*$ Logarithm Program to compute log$2$ or logarithmic of base $2*/$

$\backslash$#include $$ Stdio.h$\_>/*$ for printf and scanf functions $*/$

$\backslash$#include $$ Math.h $>/*$ for sqrt$,$ log$,$ log$2,$ etc. functions $*/$

void emptyStdin$()$;

int main$()\backslash \{$

double log$2\_$arg; $/*$ Number on which log$2$ is being computed is called argument $*/$

$/*$ Prompt with printf and int status $\backslash (=\backslash )$ scanf$(...)$ to scan user input as a double $*/$

$/*$ Validate user input and re$-$prompt$/$scanf until valid double entry is scanned $*/$

$```$

printf$("$log$2(\%\mathrm{.}1$f$)=\%\mathrm{.}2$f

$",,....,$

return $(0)$;

$\}$

vold emptyStdin$()\{$

char skip; do $\{$ scanf$("\%$c$",$ &skip$)$; $\}$ while $($skip $!=\text{'}$

$\text{'}$ && skip $!=$ EOF$)$;

$\}$

$```$