oop revised.cpp

#include <iostream>
#include <string>
using namespace std;

class Student
 {
private:
    string name;
    int rollNo;
    float marks;

public:
    // Default constructor
    Student()
     {
        name = "Unknown";
        rollNo = 0;
        marks = 0.0;
    }

    // Parameterized constructor
    Student(string n, int r, float m) {
        name = n;
        rollNo = r;
        marks = m;
    }

    // Copy constructor
    Student(const Student &s) 
    {
        name = s.name;
        rollNo = s.rollNo;
        marks = s.marks;
    }

    // Destructor
    ~Student() {
        cout << "Student " << name << " record deleted!" << endl;
    }

    // Display method
    void display() const {
        cout << "Name: " << name << ", Roll: " << rollNo << ", Marks: " << marks << endl;  }
  

    // Getter methods
    string getName() const { return name; }
    int getRollNo() const { return rollNo; }
    float getMarks() const { return marks; }


    // Setter methods using the this pointer
    void setName(string n) { this->name = n; }
    void setRollNo(int r) { this->rollNo = r; }
    void setMarks(float m) { this->marks = m; }

    // Operator overloading (+)
    Student operator+(const Student &s2) const {
        Student s3;
        s3.name = "Combined";
        s3.rollNo = 0;
        s3.marks = marks + s2.marks;
        return s3;
    }

    // Operator overloading (==)
    bool operator==(const Student &s2) const {
        return (rollNo == s2.rollNo);
    }
};
// Friend function to compare marks
void compareMarks(const Student &s1, const Student &s2)
 {
    if (s1.getMarks() > s2.getMarks())
     {
        cout << "Higher Marks: " << s1.getName() << endl;
    } else {
        cout << "Higher Marks: " << s2.getName() << endl;
    }
}
int main() {
    // s1: Default constructor
    Student s1;
    cout << "Student Records:" << endl;
    s1.display();
    // s2: Parameterized constructor
    Student s2("Alice", 101, 95.5);
    s2.display();
    // s3: Copy constructor (copy s2)
    Student s3(s2);
    s3.display();
    compareMarks(s1, s2);
    Student s4 = s1 + s2;
    cout << "Combined Marks: ";
    s4.display();
    // Check if same rollNo
    if (s2 == s3) {
        cout << "s2 and s3 have the same roll number." << endl;
    } else {
        cout << "s2 and s3 have different roll numbers." << endl;
    }

    return 0;
}