Find the space complexity for the following code. Show your answer in Big$-$O notation.

def binary$\_$search$($arr$,$ x$)$:

low $=0$

high $=$ len$($arr$)-1$

while low $<=$ high:

mid $=($low $+$ high$)//2$

if arr$[$mid$]==$ x:

return mid

elif arr$[$mid$]<$ x:

low $=$ mid $+1$

else:

high $=$ mid $-1$

return $-1$