using System;

public class Person
{
    protected int age;
    protected string name;

    public Person(string name, int age)
    {
        this.Name = name;
        this.Age = age;
    }

    public virtual string Name
    {
        get { return this.name; }
        set
        {
            if (!ValidateName(value))
            {
                throw new ArgumentException("Name’s length should not be less than 3 symbols!");
            }
            name = value;
        }
    }

    public virtual int Age
    {
        get { return this.age; }
        set
        {
            if (!ValidateAge(value))
            {
                throw new ArgumentException("Age must be positive!");
            }
            age = value;
        }
    }

    protected virtual bool ValidateName(string value)
    {
        if (value.Length < 3 || string.IsNullOrWhiteSpace(value))
        {
            return false;
        }
        return true;
    }

    protected virtual bool ValidateAge(int age)
    {
        return age >= 0;
    }

    public override string ToString()
    {
        return $"Name: {this.name}, Age: {this.age}";
    }
}


using System;

public class Child : Person
{
    public Child(string name, int age)
        : base(name, age)
    {
    }

    public override int Age
    {
        get
        {
            return base.Age;
        }
        set
        {
            if (value > 15)
            {
                throw new ArgumentException("Child's age must be less than 15!");
            }
            base.Age = value;
        }
    }

  // protected override bool ValidateAge(int age)
  // {
  //     return age < 15;
  // }
}