Написать программу про класы котов

#include <iostream>
#include <cstdlib>
 
using namespace std;
 
class TCat
{
   protected:
      size_t weight;
      size_t years;
 
   public:
      TCat(): weight(0), years(0) { ; }
      TCat(size_t theWeght, size_t theYears)
         : weight(theWeght), years(theYears) { ; }
 
      size_t GetWeight() const
      {
         return weight;
      }
 
      size_t GetYears() const
      {
         return years;
      }
 
      int CompareYears(const TCat& cat) const
      {
         return (years - cat.years);
      }
 
      int CompareWeight(const TCat& cat) const
      {
         return (weight - cat.weight);
      }
 
      TCat& DoOlder()
      {
         years++;
         return *this;
      }
 
      TCat& ChangeWeight(int change)
      {
         int newWeight = static_cast<int>(weight) + change;
 
         if (newWeight > 0)
         {
            weight = static_cast<size_t>(newWeight);
         }
 
         return *this;
      }
 
      friend ostream& operator << (ostream& out, const TCat& cat)
      {
         return (out << "weight: " << cat.weight << ", years: " << cat.years);
      }
 
      friend istream& operator >> (istream& input, TCat& cat)
      {
         return (input >> cat.weight >> cat.years);
      }
};
 
char GetCharComparisons(int value)
{
   return ((value < 0) ? '<' : ((value > 0) ? '>' : '='));
}
 
int main()
{
   TCat cat1, cat2;
 
   cout << "first cat (weight and years):  ";
   cin >> cat1;
 
   cout << "second cat (weight and years): ";
   cin >> cat2;
 
   cout << endl
        << "first:  " << cat1 << endl
        << "second: " << cat2 << endl;
 
   cout << "weight: first " << GetCharComparisons(cat1.CompareWeight(cat2)) << " second" << endl
        << "years:  first " << GetCharComparisons(cat1.CompareYears(cat2))  << " second" << endl;
 
   cat1.DoOlder().ChangeWeight(2);
   cat2.ChangeWeight(-1);
 
   cout << endl
        << "first:  " << cat1 << endl
        << "second: " << cat2 << endl;
 
   cout << "weight: first " << GetCharComparisons(cat1.CompareWeight(cat2)) << " second" << endl
        << "years:  first " << GetCharComparisons(cat1.CompareYears(cat2))  << " second" << endl;
 
   system("pause");
 
   return 0;
}