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Find Minimum in Rotated Sorted Array II

Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.

(i.e.,  [0,1,2,4,5,6,7] might become  [4,5,6,7,0,1,2]).

Find the minimum element.

The array may contain duplicates.

Example 1:

Input: [1,3,5]
Output: 1

Example 2:

Input: [2,2,2,0,1]
Output: 0

Note:

  • This is a follow up problem to Find Minimum in Rotated Sorted Array.
  • Would allow duplicates affect the run-time complexity? How and why?
Solution
/**
* @param {number[]} nums
* @return {number}
*/
var findMin = function (nums) {
var left = 0;
var right = nums.length - 1;
var mid = 0;
while (left < right) {
mid = Math.floor((left + right) / 2);
if (nums[mid] > nums[right]) {
left = mid + 1;
} else if (nums[mid] < nums[right]) {
right = mid;
} else {
right--;
}
}
return nums[left];
};

Complexity:

  • Time complexity: O(n).
  • Space complexity: O(n).