Consider this function:

boolean freaky$($n$)\{$

$//$ PRE: n is a positive integer

$//$ POST: $???$

if n $<2$:

return false

x $=2$

while x $<$ n $\{$

if n mod x $==0$

return false

x $=$ x $+1$

$\}$

return true

$\}$

$($i$)(5$ marks$)$ Find the postcondition of this function

$($ii$)(5$ marks $)$ Find the best possible big$-$oh bound for its complexity