text: class Solution {
  public:
      vector<string> findRepeatedDnaSequences(string s) {
          
          vector<string> res;
          if(s.size()<=10) return res;
          
          unordered_map<string, int> mp;
          
          int i=0;
          int j=9;
          
          while(j<s.size()){
              // cout<<i<<" "<<j<<endl;
              //cout<<s.substr(i, j-i+1)<<endl;
              mp[s.substr(i, j-i+1)]++;
              j++;
              i++;
          }
          
          for(auto& m: mp){
             // cout<<m.first<<" "<<m.second<<endl;
              if(m.second>1){
                  res.push_back(m.first);
              }
          }
          
          
          return res;
      }
  };
  