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Find Minimum in Rotated Sorted Array II

Problem​

Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,4,4,5,6,7] might become:

  • [4,5,6,7,0,1,4] if it was rotated 4 times.
  • [0,1,4,4,5,6,7] if it was rotated 7 times.

Notice that rotating an array [a[0], a[1], a[2], ..., a[n-1]] 1 time results in the array [a[n-1], a[0], a[1], a[2], ..., a[n-2]].

Given the sorted rotated array nums that may contain duplicates, return the minimum element of this array.

You must decrease the overall operation steps as much as possible.

Solution Approach​

Expected Time Complexity: O(n)O(n)

Click - to see solution code
class Solution {
public:
    int findMin(vector<int>& nums) {
        int start = 0, end = nums.size()-1;
        while(start < end){
            int mid = (start + end)/2;
            if(nums[mid] >= nums[start] && nums[end] < nums[mid]){
                start = mid + 1;
            }else if(nums[mid] >= nums[start] && nums[end] == nums[mid]){
                end -= 1;
            }else{
                end = mid;
            }
        }
        return nums[start];
    }
};