3. Implement a Calculator Class

In this exercise, you have to implement a calculator that can perform addition, subtraction, multiplication, and division.
Problem statement
Write a Python class called Calculator by completing the tasks below:
Task 1
Initializer:
Implement an initializer to initialize the values of num1 and num2
Properties:
num1
num2
Task 2
Methods:
add() is a method that returns the sum of num1 and num2.
subtract() is a method that returns the subtraction of num1 from num2.
multiply() is a method that returns the product of num1 and num2.
divide() is a method that returns the division of num2 by num1.
Input:
Pass numbers (integers or floats) in the initializer.
Output:
addition, subtraction, division, and multiplication
Sample input:

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obj = Calculator(10, 94);
obj.add()
obj.subtract()
obj.multiply()
obj.divide()

Sample method output:

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104
84
940
9.4

Coding exercise
Design a step-by-step algorithm before jumping to the implementation.

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class Calculator:
def __init__(self):
pass

def add(self):
pass

def subtract(self):
pass

def multiply(self):
pass

def divide(self):
pass

Solution

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class Calculator:
def __init__(self, num1, num2):
self.num1 = num1
self.num2 = num2

def add(self):
return (self.num2 + self.num1)

def subtract(self):
return (self.num2 - self.num1)

def multiply(self):
return (self.num2 * self.num1)

def divide(self):
return (self.num2 / self.num1)

demo1 = Calculator(10, 94)
print("Addition:", demo1.add())
print("Subtraction:", demo1.subtract())
print("Mutliplication:", demo1.multiply())
print("Division:", demo1.divide())

Explanation
We have implemented the Calculator class, which has the two properties, num1 and num2.
In the initializer, at line 3 – 4, we have initialized both properties, num1 and num2.
In line 7, we implemented add(), a method that returns the sum, num1 + num2, of both properties.
In line 10, we implemented subtract(), a method that returns the subtraction of num1 from num2.
In line 13, we implemented multiply(), a method that returns the product, num2 x num1, of both properties.
In line 16, we implemented divide(), a method that returns the division of num2 by num1.