SCNet

#include <iostream>
#include <cstring>

using namespace std;

class InvalidPassword {

private:
    char text[40];
public:
    InvalidPassword(const char *text) {

        strcpy(this->text, text);
    }
    void message() {
        cout<< text << endl;

    }

};
class InvalidEmail {
private:
    char text[40];
public:
    InvalidEmail(const char *text) {
        strcpy(this->text, text);
    }
    void message() {
        cout<< text << endl;

    }

};
class MaximumSizeLimit {

private:
    int n;
public:
    MaximumSizeLimit(int n) {
        this->n = n;
    }
    void message() {

        cout << "You can't add more than "<< n << " users." << endl;

    }

};

class User {

private:
    char username[30];
    char password[30];
    char email[30];
public:
    User(const char *_username="", const char *_password = "", const char *_email = "") {
        strcpy(username, _username);
        setPw(_password);
        setEmail(_email);

    }
    void setPw(const char *_password) {
        int upper = 0;
        int lower = 0;
        int number = 0;
        for(int i = 0; i<strlen(_password); ++i) {
            if(isupper(_password[i]))
                upper++;
            else if(islower(_password[i]))
                lower++;
            else if(isdigit(_password[i]))
                number++;
        }
        if(!upper || !lower || !number)
            throw InvalidPassword("Password is too weak.");
        strcpy(password, _password);



    }
    void setEmail(const char *mail) {
        int count = 0;
        for(int i = 0; i <strlen(mail); i++) {
            if (mail[i] == '@')
                count++;


        }
        if(count !=1)
            throw InvalidEmail("Mail is not valid.");
        strcpy(email, mail);


    }
    virtual double popularity() = 0;
};

class FacebookUser: public User {

private:
    int friends;
    int likes;
    int comments;
public:
    FacebookUser(const char *_username="", const char *_password="", const char *_email = "", const int fr = 0, const int l = 0, const int comm = 0) : User(_username, _password, _email) {

        friends = fr;
        likes = l;
        comments = comm;
    }
    double popularity() {
        return friends + likes * 0.1 + comments * 0.5;
    }
};

class TwitterUser: public User {

private:
    int followers;
    int tweets;
    static double TWEET_VALUE;
public:
    TwitterUser(const char *_username="", const char *_password ="", const char *_email="", const int fo=0, const int tw=0):User(_username, _password, _email) {
        followers = fo;
        tweets = tw;

    }
    double popularity() {
        return followers + tweets * TWEET_VALUE;
    }

};

double TwitterUser::TWEET_VALUE = 0.5;

class SocialNetwork {
private:
    User **users;
    int n;
    static int max;
public:
    SocialNetwork() {
        users = new User*[0];
        n = 0;

    }

    SocialNetwork &operator+=(User *u) {
        if(n == max) {
            throw(MaximumSizeLimit(max));
        }
        User **tmp = new User*[n+1];
        for (int i = 0; i < n; ++i)
            tmp[i] = users[i];
        tmp[n++] = u;
        delete[] users;
        users = tmp;
        return *this;
    }
    static void changeMaximumSize(int number) {
        SocialNetwork::max = number;
    }

    double avgPopularity() {
        double total = 0;
        for(int i = 0; i < n; ++i) {
            total+=users[i]->popularity();
        }
        return total / n;
    }
    ~SocialNetwork() {
        delete [] users;
    }
};


int SocialNetwork::max = 5;

int main() {

  SocialNetwork network = SocialNetwork();
    int n;
    cin >> n;
    char username[50];
    char password[50];
    char email[50];
    int userType;
    for (int i=0; i < n; ++i) {
      cin >> username;
      cin >> password;
      cin >> email;
      cin >> userType;
      if (userType == 1) {
        int friends;
        int likes;
        int comments;
        cin >> friends >> likes >> comments;

        // TODO: Try-catch
        try{
        User * u = new FacebookUser(username,password,email,friends,likes,comments);
        network += u;
        } catch(InvalidPassword &ip){
            ip.message();
        }
        catch(InvalidEmail &i){
            i.message();
        }
        catch(MaximumSizeLimit &msl){
            msl.message();
        }

      }
      else {
        int followers;
        int tweets;
        cin >> followers >> tweets;

        // TODO: Try-catch
          try{
        User * u= new TwitterUser(username,password,email,followers,tweets);
        network += u;
      	}
        catch(InvalidPassword &ip){
            ip.message();
        }
        catch(InvalidEmail &i){
            i.message();
        }
        catch(MaximumSizeLimit &msl){
            msl.message();
        }
      }

    }
    network.changeMaximumSize(6);
    cin >> username;
    cin >> password;
    cin >> email;
    int followers;
    int tweets;
    cin >> followers >> tweets;

    // TODO: Try-catch
    try{
    User * u= new TwitterUser(username,password,email,followers,tweets);
    network += u;
    }
        catch(InvalidPassword &ip){
            ip.message();
        }
        catch(InvalidEmail &i){
            i.message();
        }
        catch(MaximumSizeLimit &msl){
            msl.message();
        }

    cout << network.avgPopularity();

}