class Solution {
public:
    int findPeakElement(vector<int>& nums) {
        int left = 0, right = nums.size() - 1;
        while(left < right)
        {
            int mid = left + (right - left) / 2;
            if(nums[mid] < nums[mid + 1])
                left = mid + 1;
            else
                right = mid;
        }
        return left;
    }
};

本质和上篇最后一题一样，只是上个题找峰顶，该题找谷底；

A、D两点都可作为基准点，但A点设计边界问题

/*D为基准点*/
class Solution {
public:
    int findMin(vector<int>& nums) {
        int left = 0, right = nums.size() - 1;
        int T = nums[right];
        while(left < right)
        {
            int mid = left + (right - left) / 2;
            if(nums[mid] < T)
                right = mid;
            else
                left = mid + 1;
        }
        return nums[left];
    }
};

/*A为基准点*/
class Solution {
public:
    int findMin(vector<int>& nums) {
        int left = 0, right = nums.size() - 1;
        int T = nums[0];
        // 排除原数组
        if(T < nums[right]) return T;
        if(right == 1)  return nums[right];
        while(left < right)
        {
            int mid = left + (right - left) / 2;
            if(nums[mid] >= T)
                left = mid + 1;
            else
                right = mid;
        }
        return nums[left];
    }
};