leetcode34

class Solution {
public:
    vector<int> searchRange(vector<int>& nums, int target)
    {
        vector<int> r(, -);
        if (!nums.size())
        {
            return r;//为空时，返回[-1,-1]
        }
        int l = , h = nums.size() - , m = ;
        if (target < nums[l] || nums[h] < target)
        {
            return r; //小于最小或大于最大返回[-1,-1]
        }
        while (l <= h)
        {
            m = (l + h) / ;
            if (nums[m] == target)
            {
                //命中m时
                int i = m;
                while (nums[i] == target&&i < nums.size())
                {
                    i++;//寻找nums中与target相等值的右界
                }
                r[] = i - ;
                while (nums[m] == target&&m >= )
                {
                    m--;//寻找nums中与target相等值的左界
                }
                r[] = m + ;
                return r;
            }
            else if (nums[m] < target)
            {
                l = m + ;
            }
            else
            {
                h = m - ;
            }
        }
        return r;//没找到target，返回[-1,-1]
    }
};

补充一个python的实现：

 class Solution:
     def searchRange(self, nums: 'List[int]', target: 'int') -> 'List[int]':
         n = len(nums)
         i =
         j = n -
         if i == j:
             if nums[i] == target:
                 return [,]
             else:
                 return [-,-]
         begin =
         end = n -
         while i < j:
             if nums[i] == target:
                 begin = i
                 end = i
                 while end < n and nums[end] == target:
                     end +=
                 return [begin,end-]
             if nums[j] == target:
                 end = j
                 begin = j
                 while begin >=  and nums[begin] == target:
                     begin -=
                 return [begin+,end]
             mid = i + (j - i) //
             if nums[mid] == target:
                 begin = mid
                 while begin >=  and nums[begin] == target:
                     begin -=
                 end = mid
                 while end < n and nums[end] == target:
                     end +=
                 return [begin+,end-]
             elif nums[mid] < target:
                 i = mid +
             else:
                 j = mid -
         return [-,-]