1. ms-dos 1981
2. windows 2.0 1987
3. windows xp 2001
4. mac os 2001
5. windows 7 2009
Answer:
Your question seems incomplete
Explanation:
Answer:
i don't think there is such thing as a quasi vpn
Explanation:
Hello, you haven't provided the programing language in which you need the code, I'll explain how to do it using Python, and you can follow the same logic to make a program in the programing language that you need.
Answer:
1. # -*- coding: utf-8 -*-
2. #Python
3. class Calculator:
4. def add(self):
5. print(a + b)
6. def sub(self):
7. print(a - b)
8. def mul(self):
9. print(a * b)
10. def div(self):
11. print(a / b)
12.
13. obj = Calculator()
14. choice = 1
15. while choice != 0:
16. a = int(input("\nEnter first number: "))
17. b = int(input("Enter first number: "))
18.
19. print("\n0. EXIT")
20. print("1. DIVISION")
21. print("2. ADDITION")
22. print("3. SUBTRACTION")
23. print("4. MULTIPLICATION")
24.
25. choice = int(input("\nEnter your choice: "))
26. if choice == 1:
27. obj.div()
28. elif choice == 2:
29. obj.add()
30. elif choice == 3:
31. obj.sub()
32. elif choice == 4:
33. obj.mul()
34. else:
35. break
Explanation:
- From lines 1 to 12 we define the object with four methods, addition, subtraction, multiplication, and division. Each method contains the operation between two variables inside a print function
- On line 13 we instantiate our class
- On line 14 we declare the variable choice that is going to store the operation that the user wants to perform
- On line 15 we declare a while loop, this is going to keep running the program until the user wants to exit
- From line 16 to 18 we ask the user to enter two numbers
- From line 19 to 24 we print the possible operation, assigning a number for each operation, this indicates to the user what number to press for what operation
- On line 25 we ask the user for the operation
- From lines 26 to 35 we check the user input an accordingly we call the corresponding method to performs the operation
