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Coding Exercise

Note

If you have not configured you repository yet, please refer to this guide. You have to set it up in order to test your solutions.

Retrieving The New Problem Set

Please run

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./update

To ensure you have the latest problem set. You should be able to see 1-dynamic-memory in your repository.

The Code

This week's exercise will focus on dynamic memory, as it is a fundametal aspect of data structures in C++. Specifically, you will be allocating, handling, and freeing memory in C++. This pattern of allocating, handling, and freeing memory is essential when creating data structures (as you will see later in the course).

The 1-dynamic-memory codebase consists of a program that allows one to enroll students into a course. You will be filling in the empty functions in src/course.cpp in order complete this exercise.

Warning

In your repository, please only modify the highlighted regions in src/course.cpp indicated below

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#ifndef COURSE_H
#define COURSE_H

#include "student.h"

using namespace std;

class Course {
private:
    size_t num_students,
           max_students;
    int professor_cwid,
        class_num;
    Student *students;

public:
    Course();
    Course(size_t max);
    ~Course();

    Student get_student(size_t index) const;
    void enroll_student(const Student &student);

    // Mutators
    void set_class_number(int num);
    void set_professor_cwid(int id);

    // Accessors
    int get_class_number() const;
    size_t get_max_students() const;
    size_t get_num_students() const;
    int get_professor_cwid() const;
};

#endif

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#ifndef STUDENT_H
#define STUDENT_H

#include "string"

using namespace std;

class Student {
private:
    int cwid;
    string student_fname,
        student_lname;

public:
    // Contructors
    Student();
    Student(string fname, string lname, int id);

    // Mutators
    void set_cwid(int id);
    void set_fname(string fname);
    void set_lname(string lname);

    // Accessors
    int get_cwid () const;
    string get_fname () const;
    string get_lname () const;

    friend bool operator==(const Student &lhs, const Student &rhs);
};

#endif

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#include "course.h"
#include "student.h"
#include <stdexcept>

using namespace std;

Course::Course() {
    // Initialize member variables.
    // By default, course will hold a max of 25 students.
    // ========= ONLY MODIFY BETWEEN THE LINES  ===========



    // ====================================================
}

Course::Course(size_t max) {
    // Very similar to default constructor, but parameter specifies max
    // number of students.
    // ========= ONLY MODIFY BETWEEN THE LINES  ===========



    // ====================================================
}

Course::~Course() {
    // Utilized to free allocated memory.
    // ========= ONLY MODIFY BETWEEN THE LINES  ===========



    // ====================================================
}

Student Course::get_student(size_t index) const {
    // Fetch student at specified index.
    // Utilize stdexcept to handle edge cases.
    // ========= ONLY MODIFY BETWEEN THE LINES  ===========
    return Student();


    // ====================================================
}

void Course::enroll_student(const Student &student) {
    // Insert a new student
    // Utilize stdexcept to handle endge cases.
    // ========= ONLY MODIFY BETWEEN THE LINES  ===========



    // ====================================================
}


void Course::set_class_number(int num) {
    class_num = num;
}

void Course::set_professor_cwid(int id) {
    professor_cwid = id;
}

int Course::get_class_number() const {
    return class_num;
}

size_t Course::get_max_students() const {
    return max_students;
}

size_t Course::get_num_students() const {
    return num_students;
}

int Course::get_professor_cwid() const {
    return professor_cwid;
}

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#include "student.h"

Student::Student() : cwid(-1) {}

Student::Student(string fname, string lname, int id) :
    cwid(id), student_fname(fname), student_lname(lname) {}

void Student::set_cwid(int id) {
    cwid = id;
}

void Student::set_fname(string fname) {
    student_fname = fname;
}

void Student::set_lname(string lname) {
    student_lname = lname;
}

int Student::get_cwid() const {
    return cwid;
}

string Student::get_fname() const {
    return student_fname;
}

string Student::get_lname() const {
    return student_lname;

}

bool operator==(const Student &lhs, const Student &rhs) {
    return (lhs.cwid == rhs.cwid &&
            lhs.student_fname == rhs.student_fname &&
            lhs.student_lname == rhs.student_lname);
}

Testing

After you have modified your code, test it! You can test it by running

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./run 1-dynamic-memory

At the root of your repository.

If you've successfully implemented all of the functions, your output should look like this: 

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❯ ./run 1-dynamic-memory

================================================================================================================

                                        COMPILING 1-dynamic-memory TESTS

ar: creating archive libgtest.a
a - gtest-all.o
ar: creating archive libgtest_main.a
a - gtest-all.o
a - gtest_main.o

================================================================================================================

                                         RUNNING 1-dynamic-memory TESTS

unit_test_1
Running main() from /Users/oscar/Documents/projects/si-spring-2019/googletest/src/gtest_main.cc
[==========] Running 3 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 3 tests from Dynamic_Memory
[ RUN      ] Dynamic_Memory.Constructor
[       OK ] Dynamic_Memory.Constructor (0 ms)
[ RUN      ] Dynamic_Memory.Enroll_Student
[       OK ] Dynamic_Memory.Enroll_Student (0 ms)
[ RUN      ] Dynamic_Memory.Get_Student
[       OK ] Dynamic_Memory.Get_Student (0 ms)
[----------] 3 tests from Dynamic_Memory (0 ms total)

[----------] Global test environment tear-down
[==========] 3 tests from 1 test case ran. (0 ms total)
[  PASSED  ] 3 tests.

================================================================================================================

                                          CLEANING 1-dynamic-memory UP

================================================================================================================

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