leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
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1311.cpp (1152B)

      1 class Solution {
      2   public:
      3     vector<string> watchedVideosByFriends(vector<vector<string>> &watchedVideos, vector<vector<int>> &adj,
      4                                           int id, int level) {
      5         int n = adj.size();
      6         vector<bool> visited(n, false);
      7         queue<int> q;
      8 
      9         q.push(id);
     10         visited[id] = true;
     11         for (int lvl = 0; lvl != level; lvl++) {
     12             for (int k = q.size(); k > 0; k--) {
     13                 int id = q.front();
     14                 q.pop();
     15                 for (int c : adj[id]) {
     16                     if (!visited[c]) {
     17                         visited[c] = true;
     18                         q.push(c);
     19                     }
     20                 }
     21             }
     22         }
     23 
     24         unordered_map<string, int> freq;
     25         vector<pair<int, string>> vec;
     26         vector<string> res;
     27 
     28         for (; !q.empty(); q.pop())
     29             for (auto &st : watchedVideos[q.front()])
     30                 freq[st]++;
     31 
     32         for (auto &[k, v] : freq)
     33             vec.push_back({v, k});
     34         sort(vec.begin(), vec.end());
     35         for (auto &[_, title] : vec)
     36             res.push_back(title);
     37         return res;
     38     }
     39 };