Find Minimum in Rotated Sorted Array

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.

You may assume no duplicate exists in the array.

Solution:

public int findMin(int[] nums) {

      return findMinRec(nums, 0, nums.length-1);

    }

    

    public int findMinRec(int[] a, int start, int end) {

        while(start<end) {

            if(a[start]<a[end])

                return a[start];

            int mid = start+(end-start)/2;

            if(a[start]<=a[mid]) {

                start=mid+1;

            } else {

                end=mid;

            } 

        }

        return a[start];

    }