二分算法

public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        int[] arr = {6, 12, 33, 87, 90, 97, 108, 561};        int i = binarySearch(arr, 87);        for (int j = 0; j <arr.length ; j++) {            Log.d("hh",arr[j]+"");        }    }    public static int binarySearch(int[] arr, int x) {        int low = 0;        int high = arr.length - 1;        while (low <= high) {            int middle = (low + high) / 2;            if (x == arr[middle]) {                return middle;            } else if (x < arr[middle]) {                high = middle - 1;            } else {                low = middle + 1;            }        }        return -1;    }}