feat: add Semester Grade Calculator feature in main.cpp

Author: harshsankhla18

Src/Semester_Grade_Calculator/main.cpp

@@ -0,0 +1,136 @@
+#include <iostream>
+#include <iomanip>
+#include <vector>
+#include <string>
+#include <limits>
+
+using namespace std;
+
+class Subject {
+public:
+    string name;
+    double marks;
+    double credits;
+
+    Subject(string n = "", double m = 0, double c = 1)
+        : name(n), marks(m), credits(c) {}
+};
+
+class Calculator {
+public:
+    static string getLetterGrade(double marks) {
+        if (marks >= 90) return "A+";
+        if (marks >= 85) return "A";
+        if (marks >= 80) return "A-";
+        if (marks >= 75) return "B+";
+        if (marks >= 70) return "B";
+        if (marks >= 65) return "C+";
+        if (marks >= 60) return "C";
+        if (marks >= 50) return "D";
+        return "F";
+    }
+
+    static double gradePoint4(double marks) {
+        if (marks >= 90) return 4.0;
+        if (marks >= 85) return 3.7;
+        if (marks >= 80) return 3.5;
+        if (marks >= 75) return 3.3;
+        if (marks >= 70) return 3.0;
+        if (marks >= 65) return 2.5;
+        if (marks >= 60) return 2.0;
+        if (marks >= 50) return 1.0;
+        return 0.0;
+    }
+
+    static double gradePoint10(double marks) {
+        if (marks >= 90) return 10;
+        if (marks >= 80) return 9;
+        if (marks >= 70) return 8;
+        if (marks >= 60) return 7;
+        if (marks >= 50) return 6;
+        if (marks >= 40) return 5;
+        return 0;
+    }
+};
+
+class Semester {
+private:
+    vector<Subject> subjects;
+
+public:
+    void inputSubjects() {
+        int n;
+        cout << "Enter number of subjects: ";
+        cin >> n;
+        cin.ignore(numeric_limits<streamsize>::max(), '\n');
+
+        for (int i = 0; i < n; i++) {
+            string name;
+            double marks, credits;
+
+            cout << "\nSubject " << i + 1 << " name: ";
+            getline(cin, name);
+
+            cout << "Marks (0–100): ";
+            cin >> marks;
+            while (marks < 0 || marks > 100) {
+                cout << "Invalid marks. Enter again (0–100): ";
+                cin >> marks;
+            }
+
+            cout << "Credits (default 1): ";
+            if (!(cin >> credits)) {
+                cin.clear();
+                cin.ignore(numeric_limits<streamsize>::max(), '\n');
+                credits = 1;
+            }
+
+            cin.ignore(numeric_limits<streamsize>::max(), '\n');
+            subjects.emplace_back(name, marks, credits);
+        }
+    }
+
+    void displaySummary() {
+        double totalWeighted4 = 0, totalWeighted10 = 0, totalCredits = 0;
+
+        cout << "\n-----------------------------------------------\n";
+        cout << left << setw(12) << "Subject"
+             << setw(8) << "Marks"
+             << setw(8) << "Grade"
+             << setw(10) << "4.0 GPA"
+             << setw(10) << "10-Point" << "\n";
+        cout << "-----------------------------------------------\n";
+
+        for (auto &sub : subjects) {
+            string grade = Calculator::getLetterGrade(sub.marks);
+            double gp4 = Calculator::gradePoint4(sub.marks);
+            double gp10 = Calculator::gradePoint10(sub.marks);
+
+            cout << left << setw(12) << sub.name
+                 << setw(8) << sub.marks
+                 << setw(8) << grade
+                 << setw(10) << gp4
+                 << setw(10) << gp10 << "\n";
+
+            totalWeighted4 += gp4 * sub.credits;
+            totalWeighted10 += gp10 * sub.credits;
+            totalCredits += sub.credits;
+        }
+
+        cout << "-----------------------------------------------\n";
+        cout << " Semester GPA (4.0 scale): " 
+             << fixed << setprecision(2) << (totalWeighted4 / totalCredits) << "\n";
+        cout << " Semester GPA (10-point):  " 
+             << fixed << setprecision(2) << (totalWeighted10 / totalCredits) << "\n";
+        cout << "-----------------------------------------------\n";
+    }
+};
+
+int main() {
+    cout << "=== C++ Semester Grade Calculator ===\n";
+    Semester sem;
+    sem.inputSubjects();
+    sem.displaySummary();
+    cout << "\nThank you for using the calculator!\n";
+    return 0;
+}