java进阶 二分查找 46

 

 

 

 

package com.cyjt97.bubbling;

public class mid {
    public static void main(String[] args) {
        int arr[] = {11, 22, 33, 44, 55, 66, 77, 88, 99};
        int index = binaSeash(arr, 99);
        System.out.println(index);
    }

    private static int binaSeash(int[] arr, int num) {
        int min = 0;
        int max = arr.length - 1;
        int mid;
        while (min <= max) {
            mid = (min + max) / 2;
            if (num > arr[mid]) {
                min = mid + 1;
            } else if (num < arr[mid]) {
                max = mid - 1;
            } else {
                return mid;
            }
        }
        return -1;
    }
}