LeetCode - Find Minimum in Rotated Sorted Array II

二分查找

class Solution {
public:
    int findMin(vector<int> &num) {
        int n = num.size();
        if (n == 1)
            return num[0];
        int first = 0, last = n-1;
        while (first < last && num[first] >= num[last])
        {
            int mid = (first+last)/2;
            if (num[mid] > num[last])
                first = mid + 1;
            else if (num[mid] < num[first])
                last = mid;
            else
                first++;
        }
        return num[first];
    }
};