题解 | #二分查找-I#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param nums int整型一维数组
     * @param target int整型
     * @return int整型
     */
    public int search (int[] nums, int target) {
        return binarySearch(nums, 0, nums.length - 1, target);
    }
    private  int binarySearch(int[] nums, int left, int right, int target) {
        if (left > right) {
            return -1;
        }
        int mid = (left + right) / 2;
        if (nums[mid] == target) {
            return mid;
        } else if (nums[mid] > target) {
            return binarySearch(nums, left, mid - 1, target);
        } else if (nums[mid] < target) {
            return binarySearch(nums, mid + 1, right, target);
        } else {
            return -1;
        }
    }
}