题目
给出第一个词 first 和第二个词 second,考虑在某些文本 text 中可能以 “first second third” 形式出现的情况,其中 second 紧随 first 出现,third 紧随 second 出现。
对于每种这样的情况,将第三个词 “third” 添加到答案中,并返回答案。
示例 1:
输入:text = "alice is a good girl she is a good student", first = "a", second = "good" 输出:["girl","student"]
示例 2:
输入:text = "we will we will rock you", first = "we", second = "will" 输出:["we","rock"]
解题
方法一:split成数组+一次遍历
class Solution { public: vector<string> findOcurrences(string text, string first, string second) { //split vector<string>strs; int n=text.size(); int i=0; while(i<n){ int start=i; while(i<n&&text[i]!=' ') i++; strs.push_back(text.substr(start,i-start)); while(i<n&&text[i]==' ') i++; } //一次遍历得到结果 int p=0; vector<string> res; while(p+2<strs.size()){ if(strs[p]==first&&strs[p+1]==second) res.push_back(strs[p+2]); p++; } return res; } };