turn $=0$

Thread$1$

While $($true$)\{$

While$($turn $==1)$;

$/*$ start of critical section $*/$

$/*$ end of critical section $*/$

turn $=1$;

$\}$

Thread$2$

While $($true$)\{$

While$($turn $==0)$;

$/*$ start of critical section $*/$

$/*$ end of critical section $*/$

turn $=0$;

$\}$