C++ Object-Oriented Programming: Student information and grade calculation

C++ Object oriented programming: Exercise-9 with Solution

Write a C++ program to implement a class called Student that has private member variables for name, class, roll number, and marks. Include member functions to calculate the grade based on the marks and display the student's information.

Sample Solution:

C Code:

#include <iostream> // Include necessary header for input/output stream
#include <string> // Include necessary header for string handling

class Student { // Define a class named Student
  private: 
    std::string name; // Private member variable to store student's name
    std::string studentClass; // Private member variable to store student's class
    int rollNumber; // Private member variable to store student's roll number
    double marks; // Private member variable to store student's marks

  public:
    // Constructor to initialize Student object with provided details
    Student(const std::string & studentName, const std::string & sClass, int rollNum, double studentMarks)
        : name(studentName), studentClass(sClass), rollNumber(rollNum), marks(studentMarks) {}

    // Member function to calculate the grade based on marks
    std::string calculateGrade() {
      if (marks >= 90) {
        return "A+";
      } else if (marks >= 80) {
        return "A";
      } else if (marks >= 70) {
        return "B";
      } else if (marks >= 60) {
        return "C";
      } else {
        return "D";
      }
    }

    // Member function to display student information
    void displayInformation() {
      std::cout << "\n\nName: " << name << std::endl; // Output student's name
      std::cout << "Class: " << studentClass << std::endl; // Output student's class
      std::cout << "Roll Number: " << rollNumber << std::endl; // Output student's roll number
      std::cout << "Marks: " << marks << std::endl; // Output student's marks
      std::cout << "Grade: " << calculateGrade() << std::endl; // Output student's grade
    }
};

int main() {
  // Create a student object
  std::string studentName; // Variable to store student's name
  std::string sClass; // Variable to store student's class
  int rollNum; // Variable to store student's roll number
  double studentMarks; // Variable to store student's marks

  std::cout << "Student details: "; // Prompt user for student details
  std::cout << "\nName: "; // Prompt user for student's name
  std::getline(std::cin, studentName); // Input student's name

  std::cout << "Class: "; // Prompt user for student's class
  std::getline(std::cin, sClass); // Input student's class

  std::cout << "Roll number: "; // Prompt user for student's roll number
  std::cin >> rollNum; // Input student's roll number

  std::cout << "Marks (0-100): "; // Prompt user for student's marks
  std::cin >> studentMarks; // Input student's marks

  Student student(studentName, sClass, rollNum, studentMarks); // Create Student object with provided details

  // Display student information
  student.displayInformation(); // Output student's information

  return 0; // Return 0 to indicate successful completion
}

Sample Output:

Student details:
Name: Ljubinka Marquita
Class: V
Roll number: 2
Marks (0-100): 98


Name: Ljubinka Marquita
Class: V
Roll Number: 2
Marks: 98
Grade: A+

Student details:
Name: Lia Chimezie
Class: VI
Roll number: 8
Marks (0-100): 88


Name: Lia Chimezie
Class: VI
Roll Number: 8
Marks: 88
Grade: A

Explanation:

In the above exercise,

• The Student class is defined with private member variables name, studentClass, rollNumber, and marks representing the student's name, class, roll number, and marks.
• The constructor Student initializes the name, studentClass, rollNumber, and marks member variables.
• The member function calculateGrade calculates the grade based on the marks. It checks the marks against different ranges and returns the corresponding grade character.
• The member function displayInformation displays the student's information, including name, class, roll number, marks, and grade.
• In the main function, the user inputs the student's name, class, roll number, and marks.
• An instance of the Student class is created using the provided values.
• The displayInformation member function is called on the student object to display the student's information, including the calculated grade.

Flowchart:

CPP Code Editor:

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