Find Minimum in Rotated Sorted Array

Desicription

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.

Example 1:

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Input: [3,4,5,1,2]
Output: 1

Example 2:

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Input: [4,5,6,7,0,1,2]
Output: 0

Solution

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class Solution {
public:
int findMin(vector<int>& nums) {
int left = 0;
int right = nums.size()-1;
while(left < right) {
if(nums[left] < nums[right])
return nums[left];
int mid = (left + right) >> 1;
if(nums[left] <= nums[mid])
left = mid + 1;
else
right = mid;
}
return nums[left];
}
};