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Find Minimum in Rotated Sorted Array

Problem statement

Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,2,4,5,6,7] might become:

  • [4,5,6,7,0,1,2] if it was rotated 4 times.
  • [0,1,2,4,5,6,7] 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 of unique elements, return the minimum element of this array.

You must write an algorithm that runs in O(log n) time.

Example 1:

Input: nums = [3,4,5,1,2]Output: 1Explanation: The original array was [1,2,3,4,5] rotated 3 times.

Example 2:

Input: nums = [4,5,6,7,0,1,2]Output: 0Explanation: The original array was [0,1,2,4,5,6,7] and it was rotated 4 times.

Example 3:

Input: nums = [11,13,15,17]Output: 11Explanation: The original array was [11,13,15,17] and it was rotated 4 times. 

Constraints:

  • n == nums.length
  • 1 <= n <= 5000
  • -5000 <= nums[i] <= 5000
  • All the integers of nums are unique.
  • nums is sorted and rotated between 1 and n times.

My solution

/**
* @param {number[]} nums
* @return {number}
*/
var findMin = function(nums) {
const len = nums.length;

if (len === 1) {
return nums[0]
}

let left = 0;
let right = len - 1;

while (left < right) {
const mid = Math.floor((right + left) / 2);

const num = nums[mid];
const lNum = nums[left];
const rNum = nums[right];

if (num > lNum && num > rNum) {
if (lNum < rNum) {
right = mid - 1
} else {
left = mid + 1;
}
} else {
if (num > nums[mid + 1]) {
left = mid + 1
} else {
right = mid;
}
}

}

return nums[left];
};