leetcode_c++： Find Minimum in Rotated Sorted Array （153）

题目

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.

在一个旋转过的有序数组中找最小的数

算法

O(logn)

class Solution {
public:
int findMin(vector<int>& nums) {
int left=0,right=nums.size()-1;

int mid;
while(left<=right){
mid=left+(right-left)/2;
if(nums[left]<=nums[mid] && nums[mid]<=nums[right]){
return nums[left];
}else if(nums[left]<=nums[mid]){
left=mid+1;
}else{
right=mid;
}
}
return nums[0];
}
};