磊磊零基础打卡算法：day01

5.1

二分查找

 

• 主要思路：左变量，右变量，中间变量

• 易错点，这里我只写一种left<right

• 具体做法：如果mid小于target；left+1变成mid；否则right变成mid；

class Solution {
    public int search(int[] nums, int target) {
        int left =0;
        int right =nums.length;
        while(left<right){
            int mid = (left +right)/2;
            if(nums[mid]>target){
                right = mid ;
            }else if(nums[mid ] <target){
                left = mid +1;
            }else{
                return mid;
            }
            }return -1;
    }
}