low + ( high - low ) / 2 ;
$ mid = ( int ) ( ( $ low + $ high ) / 2 ) ; if ( $ mid == $ arr [ $ mid ] ) return $ mid ; if ( $ mid > $ arr [ $ mid ] ) return binarySearch ( $ arr , ( $ mid + 1 ) , $ high ) ; else return binarySearch ( $ arr , $ low , ( $ mid - 1 ) ) ; }