一、题目内容

二、题解

解法1：

思路

二分

代码

public class Solution {
    public int search (int[] nums, int target) {
        // write code here
        if (nums == null || nums.length < 1) {
           return -1;
        }
        if (nums.length == 1) {
            return nums[0] == target ? 0 : -1;
        }
        int left = 0,right = nums.length-1;
        while(left<=right){
            int mid = (left + right) >> 1;
            if (nums[mid] == target) {
               return mid;
            }
            //左侧升序
            if (nums[0] <= nums[mid]) {
                if (target >= nums[0] && target < nums[mid]) {
                    right = mid - 1;
                }else{
                    left = mid + 1;
                }
            }else{
                if (target > nums[mid] && target <= nums[right]) {
                   left = mid + 1;
                } else {
                    right = mid - 1;
                }
            }  
        }
        return -1;
    }
}