added third assignment

calculator2.py

+print("Simple Calculator in Python")
+
+firstnumber = float(input("Enter first number: "))
+secondnumber = float(input("Enter second number: "))
+
+print("Select operation:")
+print("1. Addition")
+print("2. Subtraction")
+print("3. Multiplication")
+print("4. Division")
+print("5. Mod")
+
+choice = input("Enter choice (1/2/3/4/5): ")
+
+if choice == "1":
+    result = firstnumber + secondnumber
+elif choice == "2":
+    result = firstnumber - secondnumber
+elif choice == "3":
+    result = firstnumber * secondnumber
+elif choice == "4":
+    if secondnumber == 0:
+        result = "Error: Cannot divide by zero"
+    else:
+        result = firstnumber / secondnumber
+elif choice == "5":
+    result = firstnumber % secondnumber
+else:
+    result = "Invalid operation"
+
+print("Result:", result)

studentmanagement.py

+class Student:
+    def __init__(self, roll_no, name, marks):
+        self.roll_no = roll_no
+        self.name = name
+        self.marks = marks
+
+    def display(self):
+        print(f"Roll No: {self.roll_no}, Name: {self.name}, Marks: {self.marks}")
+
+
+class StudentManagementSystem:
+    def __init__(self):
+        self.students = []
+
+    def add_student(self):
+        roll_no = input("Enter Roll No: ")
+        name = input("Enter Name: ")
+        marks = float(input("Enter Marks: "))
+        student = Student(roll_no, name, marks)
+        self.students.append(student)
+        print("Student added successfully!")
+
+    def display_students(self):
+        if not self.students:
+            print("No students to display.")
+        else:
+            print("\n--- Student List ---")
+            for student in self.students:
+                student.display()
+
+    def search_student(self):
+        roll_no = input("Enter Roll No to search: ")
+        for student in self.students:
+            if student.roll_no == roll_no:
+                print("Student found:")
+                student.display()
+                return
+        print("Student not found.")
+
+    def delete_student(self):
+        roll_no = input("Enter Roll No to delete: ")
+        for student in self.students:
+            if student.roll_no == roll_no:
+                self.students.remove(student)
+                print("Student deleted successfully!")
+                return
+        print("Student not found.")
+
+
+def main():
+    sms = StudentManagementSystem()
+
+    while True:
+        print("\n====== Student Management System ======")
+        print("1. Add Student")
+        print("2. Display Students")
+        print("3. Search Student")
+        print("4. Delete Student")
+        print("5. Exit")
+
+        choice = input("Enter your choice (1-5): ")
+
+        if choice == "1":
+            sms.add_student()
+        elif choice == "2":
+            sms.display_students()
+        elif choice == "3":
+            sms.search_student()
+        elif choice == "4":
+            sms.delete_student()
+        elif choice == "5":
+            print("Exiting... Goodbye!")
+            break
+        else:
+            print("Invalid choice! Please select between 1-5.")
+
+
+if __name__ == "__main__":
+    main()