[leetcode]81. Search in Rotated Sorted Array II旋转过有序数组里找目标值II(有重)

This is a follow up problem to Search in Rotated Sorted Array, where nums may contain duplicates.

 

思路

该题是[leetcode]33. Search in Rotated Sorted Array旋转过有序数组里找目标值 的followup

唯一区别是加了line24-26的else语句来skip duplicates

 

代码

class Solution {
    public boolean search(int[] nums, int target) {
         // corner case
        if (nums.length == 0) return false;
        // init
        int left = 0;
        int right = nums.length - 1;

        while (left <= right) {
            int mid = left + (right - left) / 2;
            if (nums[mid] == target) return true;
            else if (nums[mid] < nums[right]) { // right side is sorted
                if (target > nums[mid] && target <= nums[right]) {
                    left = mid + 1;
                } else {
                    right = mid - 1;
                }
            } else if(nums[mid] > nums[right]){ // left side is sorted 
                if (target < nums[mid] && target >= nums[left]) {
                    right = mid - 1;
                } else {
                    left = mid + 1;
                }
            }else{
               right--; //skip duplicats 
            }
        }
        return false;
    }   
}