main.cpp

#include <iostream>
#include <iomanip>
#include <fstream>
#include <cctype>
using namespace std;

// Convert grade to uppercase safely
string normalizeGrade(string g) {
    for (char &c : g) {
        c = toupper(c);
    }
    return g;
}

// Convert grade to grade points
double getGradePoint(string grade) {

    if (grade == "A") return 4.0;
    if (grade == "A-") return 3.7;
    if (grade == "B+") return 3.3;
    if (grade == "B") return 3.0;
    if (grade == "B-") return 2.7;
    if (grade == "C+") return 2.3;
    if (grade == "C") return 2.0;
    if (grade == "D") return 1.0;
    if (grade == "F") return 0.0;

    return -1;
}

int main() {

    ofstream file("cgpa_report.txt");

    if (!file) {
        cout << "Error creating file!\n";
        return 0;
    }

    int semesters;

    cout << "Enter number of semesters: ";
    if (!(cin >> semesters) || semesters <= 0) {
        cout << "Invalid number of semesters.\n";
        return 0;
    }

    double totalAllCredits = 0;
    double totalAllGradePoints = 0;

    cout << fixed << setprecision(2);
    file << fixed << setprecision(2);

    file << "============================\n";
    file << "      CGPA REPORT\n";
    file << "============================\n\n";

    for (int s = 1; s <= semesters; s++) {

        cout << "\nSemester " << s << endl;

        file << "\n============================\n";
        file << "Semester " << s << "\n";
        file << "============================\n";

        int courses;

        cout << "Enter number of courses in Semester " << s << ": ";
        if (!(cin >> courses) || courses <= 0) {
            cout << "Invalid number of courses.\n";
            return 0;
        }

        double semesterCredits = 0;
        double semesterGradePoints = 0;

        for (int i = 1; i <= courses; i++) {

            string grade;
            double creditHours;

            cout << "\nCourse " << i << endl;

            cout << "Enter Grade (A, A-, B+ etc): ";
            cin >> grade;
            grade = normalizeGrade(grade);

            double gradePoint = getGradePoint(grade);

            if (gradePoint < 0) {
                cout << "Invalid grade entered. Program stopped.\n";
                return 0;
            }

            cout << "Credit Hours: ";
            if (!(cin >> creditHours) || creditHours <= 0) {
                cout << "Invalid credit hours.\n";
                return 0;
            }

            double coursePoints = gradePoint * creditHours;

            semesterCredits += creditHours;
            semesterGradePoints += coursePoints;

            cout << "Course " << i << " Points = " << coursePoints << endl;

            file << "Course " << i
                 << " | Grade: " << grade
                 << " | Credit Hours: " << creditHours
                 << " | Grade Point: " << gradePoint
                 << " | Total Points: " << coursePoints << "\n";
        }

        if (semesterCredits == 0) {
            cout << "Semester credits cannot be zero.\n";
            return 0;
        }

        double semesterGPA = semesterGradePoints / semesterCredits;

        cout << "Semester GPA: " << semesterGPA << endl;

        file << "\nSemester Credits: " << semesterCredits << "\n";
        file << "Semester Grade Points: " << semesterGradePoints << "\n";
        file << "Semester GPA: " << semesterGPA << "\n";

        totalAllCredits += semesterCredits;
        totalAllGradePoints += semesterGradePoints;
    }

    if (totalAllCredits == 0) {
        cout << "No valid data to calculate CGPA.\n";
        return 0;
    }

    double cgpa = totalAllGradePoints / totalAllCredits;

    cout << "\nFINAL CGPA: " << cgpa << endl;

    file << "\n============================\n";
    file << "FINAL SUMMARY\n";
    file << "============================\n";

    file << "Total Credits: " << totalAllCredits << "\n";
    file << "Total Grade Points: " << totalAllGradePoints << "\n";
    file << "Final CGPA: " << cgpa << "\n";

    file.close();

    cout << "\nReport saved as cgpa_report.txt\n";

    return 0;
}