题解 | #二分查找-I#

import java.util.*;


public class Solution {

    int res = -1;

    /**
     * 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) {
        // write code here
        if(nums.length == 0) return -1;
        two(nums,target,0,nums.length);
        return res;
    }
    private void two(int[] nums,int target,int left,int right){
        if(left >= right) return;
        int mid = left + ( (right - left) >> 1 );
        if (nums[mid] < target) two(nums,target,mid+1,right);
        else if(nums[mid] > target) two(nums,target,left,mid);
        else {
            res = mid;
            return;
        }
    } 
}