WEEK 10 · LAB 4

Lab 4 — Objects and Classes

Create two student objects and display their information.

I. Objectives

Use a class to group a student's name and score.
Initialize an object with a constructor and call a member function.

Before the Lab

Week 9: std::string, public and private members, constructors, and const member functions. A constructor sets up an object; show() const displays its data without changing its data members.

II. Environment

A computer with Windows, macOS, or Linux.
Use OnlineGDB in C++ mode, or the C++ environment demonstrated in class.
Save your program as lab04.cpp. Use one source file for this lab.

Open OnlineGDB ↗

III. Tasks and Requirements

Complete the TODOs in the starter code, then compare your result with the expected output. The starter is intentionally unfinished.

Task 1 — Read the Student class

Find the private data members name and score. Find the constructor and show(). Run the starter; it will not display student information until the TODOs are completed.

Task 2 — Complete the constructor and show()

At TODO 1, assign studentName to name and studentScore to score. At TODO 2, print the name and score on one line, as shown below.

Task 3 — Test two independent objects

Run the program for Alex (85) and Sam (92). Then change only Sam's score to 70 and run it again. Alex's score should still be 85.

Starter Code

Download .cpp

#include <iostream>
#include <string>

class Student {
private:
    std::string name;
    int score = 0;

public:
    Student(std::string studentName, int studentScore) {
        // TODO 1: Set name and score.
    }

    void show() const {
        // TODO 2: Print name and score.
    }
};

int main() {
    Student first("Alex", 85);
    Student second("Sam", 92);
    first.show();
    second.show();
    return 0;
}

Expected Output

Expected output after completing both TODOs.

Alex 85
Sam 92

IV. Submission

Your completed lab04.cpp source file.
One or two screenshots showing your test results.
A short answer to each question below, in English or Chinese.

Two Short Questions

When is the Student constructor called?
Why can first and second store different scores?