Не могу понять ,что означают строки

#include "pch.h"
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <algorithm>
#include <ctime>
#include <cstdlib> 
using namespace std;
class Critter
{
public:
    static int s_Total;     //static member variable declaration
                            //total number of Critter objects in existence
 
    Critter(int hunger = 0);
    static int GetTotal();  //static member function prototype
 
private:
    int m_Hunger;
};
 
int Critter::s_Total = 0;   //static member variable initialization
 
Critter::Critter(int hunger):
m_Hunger(hunger)
{
    cout << "A critter has been born!" << endl;
    ++s_Total;
}
 
int Critter::GetTotal()     //static member function definition
{
    return s_Total;
}
 
int main()
{
    cout << "The total number of critters is: ";
    cout << Critter::s_Total << "\n\n";
 
    Critter crit1, crit2, crit3;
 
    cout << "\nThe total number of critters is: ";
    cout << Critter::GetTotal() << "\n";
 
    return 0;
}

Critter::Critter(int hunger): //Описание конструктора класса с параметром int hunger
m_Hunger(hunger) //Инициализация переменной m_Hunger внутри данного класса значением hunger

m_Hunger(hunger)

Critter::Critter(int hunger)
{
    m_Hunger = hunger;
    cout << "A critter has been born!" << endl;
    ++s_Total;
}

Critter::Critter(int hunger):
m_Hunger(hunger)
{
    cout << "A critter has been born!" << endl;
    ++s_Total;
}