旋转数组中的二分查找

 

 

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