Fastest and easiest in-place C++ solution using STL
The code is pretty self-explanatory due to variable names.\n\nint numUniqueEmails(vector<string>& emails)\n    {\n        for(auto& email:emails){\n            
The code is pretty self-explanatory due to variable names.\n```\nint numUniqueEmails(vector<string>& emails)\n    {\n        for(auto& email:emails){\n            auto at_location = find(email.begin(),email.end(),\'@\');\n            auto end_after_removing_dots = remove(email.begin(),at_location,\'.\');\n\t\t\tauto plus_location = find(email.begin(),end_after_removing_dots,\'+\');\n            email.erase(plus_location,at_location);\n        }\n        return unordered_set(emails.begin(),emails.end()).size();\n    }\n```\nIf you have any doubts or suggestions, feel free to comment.\nIf you found this solution useful, you know where the upvote is :)
['C', 'C++']