leetcode34

class Solution {
public:
    vector<int> searchRange(vector<int>& nums, int target)
    {
        vector<int> r(2, -1);
        if (!nums.size())
        {
            return r;//为空时，返回[-1,-1]        
        }
        int l = 0, h = nums.size() - 1, m = 0;
        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) / 2;
            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[1] = i - 1;
                while (nums[m] == target&&m >= 0)
                {
                    m--;//寻找nums中与target相等值的左界                
                }
                r[0] = m + 1;
                return r;
            }
            else if (nums[m] < target)
            {
                l = m + 1;
            }
            else
            {
                h = m - 1;
            }
        }
        return r;//没找到target，返回[-1,-1]    
    }
};