Thread$1$

While $($true$)\{$

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

turn $=1$;

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

$\frac{?}{?}**$ end of critical section $*/$

turn $=0$;

$\}$

Thread$2$

While $($true$)\{$

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

turn $=1$;

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

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

turn $=0$;

$\}$

Mutual exclusion

Progress

Bounded waiting

None of the above