Person / Pupil classes 2

#include <iostream>
#include <string>

using namespace std;

class Person{
  public:
    string name, birthDate;

    Person(string name, string date){
      this->name = name;
      this->birthDate = date;
    }

    void print(){
      cout << "Person: {Name: " << name << ", Birth Date: " << birthDate << "}";
    }
};

class Teacher : public Person{
  public:
    string category, classes[36];

    Teacher(string name, string date, string category, string classes[], int classesLength) : Person(name, date){
      this->category = category;
      if(classesLength <= 36) for(int i = 0; i < classesLength; i ++) this->classes[i] = classes[i];
    }

    void print(){
      cout << "Teacher: {Name: " << name << ", Birth Date: " << birthDate << ", Category: " << category << ", Classes: ";
      for(int i = 0; i < 36; i++){
        if(classes[i] == " ") break;
        else cout << classes[i] << " ";
      }
      cout << "}";
    }

    void next(){
      string newClasses[36];
      int index = 0;
      for(int i = 0; i < 36; i ++){
        string element = classes[i];
        int c = stoi(element.substr(0, element.length() - 1)) + 1;
        if(c < 11){
          newClasses[index] = to_string(c) + element.substr(element.length() - 1, 1);
          index++;
        }
      }
      for(int i = 0; i < index; i++) classes[i] = newClasses[i];
    }
};

class Pupil : public Person{
  public:
    string project, m_class;

    Pupil(string name, string date, string project, string theClass) : Person(name, date){
      this->project = project;
      this->m_class = theClass;
    }

    void print(){
      cout << "Pupil: {Name: " << name << ", Birth Date: " << birthDate << ", Class: " << m_class << ", Project: " << project << "}";
    }
};

int main(){
  string classes[5] = {"10A", "11A", "5B"};
  Teacher teacher = new Teacher("Teacher's Name", "10.10.2010", "Biology", classes, 5)
}