Leetcode-Find Minimum in Rotated Sorted Array

Suppose a sorted array 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.

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Analysis:

Use the similar method used in "search in roated sorted array".

Solution:

public class Solution {
    public int findMin(int[] num) {
        if (num.length==0) return -1;

        int start = 0, end = num.length-1;
        int mid = -1;

        while (start!=end-1){
            mid = (start+end)/2;

            if (num[mid]<num[start]){
                end = mid;
                continue;
            }

            if (num[mid]>num[end]){
                start = mid;
                continue;
            }

            return num[start];
        }
        
        if (num[start]>num[end]) return num[end];
        else return num[start];

    }
}