What is the average case complexity of the isqrt$()$ function?

It has a worst$-$case complexity of

$.$

"rand.nextInt$($k$)"$ generates a random number in the range $0..$k$-1$ and runs in O$(1)$ time$).$

Random rand $=$ new Random$()$;

$...$

int isqrt$($int x$)\{$

int k $=0$;

while $(($k$+1)*($k$+1)<=$ x $||$ k$*$k $>$ x$)\{$

k $=$ rand.nextInt$($x$)$;

$\}$

return k;

$\}$