Leetcode-5083 Occurrences After Bigram(Bigram 分词)

#define _for(i,a,b) for(int i = (a);i < b;i ++)

class Solution
{
    public:
        vector<string> findOcurrences(string text, string first, string second)
        {
            vector<string> rnt;
            vector<string> li;
            string tmp;
            int i = 0;
            while(i < text.size())
            {
                while(text[i] != ' ' && i < text.size())
                {
                    tmp += text[i];
                    i ++;
                }
                i ++;
                li.push_back(tmp);
                tmp.clear();
            }
            _for(j,0,li.size())
            {
                if(li[j]==first && j+1 < li.size() && li[j+1]==second)
                {
                    if(j+2<li.size())
                        rnt.push_back(li[j+2]);
                }
            }
            return rnt;
        }
};