Uncommon Words from Two Sentences

Problem Statement - link #

A sentence is a string of single-space separated words where each word consists only of lowercase letters.

A word is uncommon if it appears exactly once in one of the sentences, and does not appear in the other sentence.

Given two sentences s1 and s2, return a list of all the uncommon words. You may return the answer in any order.

Examples #

Example 1:

Input: s1 = "this apple is sweet", s2 = "this apple is sour"
Output: ["sweet","sour"]

Example 2:

Input: s1 = "apple apple", s2 = "banana"
Output: ["banana"]

Constraints #

• 1 <= s1.length, s2.length <= 200
• s1 and s2 consist of lowercase English letters and spaces.
• s1 and s2 do not have leading or trailing spaces.
• All the words in s1 and s2 are separated by a single space.

Solutions #

class Solution {
public:
    vector<string> uncommonFromSentences(string s1, string s2) {
      vector<string> res;
      map<string,int> m1;
      string ss = s1 + " " + s2;
      stringstream s(ss);
      string x;
      while( s >> x ) m1[x]++;
      for(auto i: m1) 
        if(i.second == 1)
          res.push_back(i.first);      
      return res;
    }
};