[LeetCode] Find Minimum in Rotated Sorted Array-白红宇

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.

解题思路
二分查找

实现代码

/*************************************************************    *  @Author   : 楚兴    *  @Date     : 2015/2/8 17:17    *  @Status   : Accepted    *  @Runtime  : 10 ms*************************************************************/#include 
     
      #include 
      
       using namespace std;class Solution {public:    int findMin(vector
       
         &num) {        int begin = 0;        int end = num.size() - 1;        int mid;        while (begin + 1 < end)        {            mid = (begin + end) / 2;            if (num[mid] > num[end])            {                begin = mid;            }            else            {                end = mid;            }        }        return num[begin] < num[end] ? num[begin] : num[end];    }};int main(){    Solution s;    vector
        
          nums;    nums.push_back(4);    nums.push_back(5);    nums.push_back(6);    nums.push_back(7);    nums.push_back(1);    nums.push_back(2);    nums.push_back(3);    cout<
         
          <

根据官方解答优化后的代码：

/*************************************************************    *  @Author   : 楚兴    *  @Date     : 2015/2/8 17:46    *  @Status   : Accepted    *  @Runtime  : 7 ms*************************************************************/#include 
     
      #include 
      
       using namespace std;class Solution {public:    int findMin(vector
       
         &num) {        int begin = 0;        int end = num.size() - 1;        int mid;        while (begin < end)        {            mid = (begin + end) / 2;            if (num[mid] > num[end])            {                begin = mid + 1;            }            else            {                end = mid;            }        }        return num[begin];    }};