Coding Exercise 28: Creating and Accessing Objects

We have already declared a C++ class named Dog that is located in Dog.h file (we'll learn about header files later in this section)

In the test_dog function create a dog object named spot and, using the . operator, set the name attribute to the string "Spot" and the age attribute to 5.

#include "Dog.h"

Dog test_dog() {
//---- WRITE YOUR CODE BELOW THIS LINE----

Dog spot;

spot.name = "Spot";
spot.age = 5;

//---- WRITE YOUR CODE ABOVE THIS LINE----
//---- DO NOT CHANGE THE CODE BELOW----
    return spot;
}

Coding Exercise 29: Adding public methods that access private class attributes

Given the following Dog class in Dog.h add the following public getter and setter methods that get and set each class attribute as follow:

get_name return the name attribute of the dog set_name sets the name attribute of the dog to the string that is passed into the method get_age returns the age attribute of the dog set_age sets the age attribute of the dog to the int that is passed into the method

Dog.h file:

#ifndef __DOG_H__
#define __DOG_H__
#include <string>
using namespace std;

class Dog {
private:
    string name;
    int age;
public:

//---- WRITE YOUR CLASS FUNCTIONS BELOW THIS LINE----
    string get_name() {
        return name;
    }

    void set_name(string n) {
        name = n;
    }

    int get_age() {
        return age;
    }

    void set_age(int a) {
        age = a;
    }

//---- WRITE YOUR CLASS FUNCTIONS ABOVE THIS LINE----
};
#endif 

Coding Exercise 30: Adding more public methods to an existing class

Given an existing Dog class in Dog.h, add the following public method to the class: get_human_years() return the dog's age ultiplied by 7 speak() returns the std::string "Woof"

Dog.h file:

#ifndef __DOG_H__
#define __DOG_H__
#include <string>
using namespace std;

class Dog {
private:
    string name;
    int age;
public:

    string get_name() {return name; }
    void set_name(string n) {name = n; }
    int get_age() {return age; }
    void set_age(int a) { age = a;}
    //---- WRITE YOUR CLASS FUNCTIONS BELOW THIS LINE----
    
    int get_human_years() {
        return age*7;
    }

    string speak() {
        // return string("Woof");       // works too
        string woof = "Woof";
        return (woof);
    }

    //---- WRITE YOUR CLASS FUNCTIONS ABOVE THIS LINE----
};
#endif 

Coding Exercise 31: Add a Default Constructor to an Existing Class

Given the Dog class in Dog.h, add a default no-args constructor that initializes the dog's name to "None" and hte dog's age to zero.

Dog.h file:

#ifndef __DOG_H__
#define __DOG_H__
#include <string>
using namespace std;

class Dog {
private:
    string name;
    int age;
public:
//---- WRITE YOUR NO-ARGS CONSTRUCTOR BELOW THIS LINE----

    Dog() {
        name = "None";
        age = 0;
    }

//---- WRITE YOUR NO_ARGS CONSTRUCTOR ABOVE THIS LINE----
//---- DO NOT MODIFY THE CODE BELOW THIS LINE


    string get_name() {return name; }
    void set_name(string n) {name = n; }
    int get_age() {return age; }
    void set_age(int a) { age = a;}
    int get_dog_years() { return age * 7; }
    string speak() { return "Woof";}
};

#endif 

Coding Exercise 32: Add an Overloaded Constructor to an Existing Class

Given the Dog class in Dog.h, add an overloaded constructor that expect a std::string and int as parameters

The constructor should allow us to create Dog objects as follows

Dog fido {"Fido", 4};
Dog spot {"Spot", 5};

Dog.h file:

#ifndef __DOG_H__
#define __DOG_H__
#include <string>
using namespace std;

class Dog {
private:
    string name;
    int age;
public:

//---- WRITE YOUR OVERLOADED CONSTRUCTOR BELOW THIS LINE
    
    Dog(string name_val, int age_val) {
        name = name_val;
        age = age_val;
    }

//---- WRITE YOUR OVERLOADED CONSTRUCTOR ABOVE THIS LINE
    string get_name() {return name; }
    void set_name(string n) {name = n; }
    int get_age() {return age; }
    void set_age(int a) { age = a;}
    int get_dog_years() { return age * 7; }
    string speak() { return "Woof";}
};
#endif

Coding Exercise 33: Add a Copy Constructor to an Existing Class

Given the Dog class in Dog.h, add an copy constructor.

The copy constructor should copy the attributes from one object to another. Also, display "Copy Constructor" to cout in the body of copy constructor. Do NOT follow the outpult statment with \n or endl.

The copy constructor should allow us to create Dog object as follows:

Dog spot {"Spot", 5};       // Overloaded constructor
Dog twin {spot};            // Copy constructor, twin will be a copy of spot

Dog.h file

#ifndef __DOG_H__
#define __DOG_H__
#include <string>
using namespace std;

class Dog {
private:
    string name;
    int age;
public:
    Dog(string name, int age) : name{name}, age{age} { }

//---- WRITE YOUR COPY CONSTRUCTOR BELOW THIS LINE

    Dog(const Dog &source) 
        : Dog {source.name, source.age} {
            cout << "Copy Constructor";
        }

//---- WRITE YOUR COPY CONSTRUCTOR ABOVE THIS LINE
    string get_name() {return name; }
    void set_name(string n) {name = n; }
    int get_age() {return age; }
    void set_age(int a) { age = a;}
    int get_dog_years() { return age * 7; }
    string speak() { return "Woof";}
};
#endif