Python Program - Make a Simple Calculator

here's a Python program that makes a simple calculator:

# function to add two numbers
def add(x, y):
    return x + y

# function to subtract two numbers
def subtract(x, y):
    return x - y

# function to multiply two numbers
def multiply(x, y):
    return x * y

# function to divide two numbers
def divide(x, y):
    return x / y

# get input from user
print("Select operation.")
print("1. Add")
print("2. Subtract")
print("3. Multiply")
print("4. Divide")

choice = input("Enter choice (1/2/3/4): ")

num1 = float(input("Enter first number: "))
num2 = float(input("Enter second number: "))

# perform selected operation
if choice == '1':
    print(num1, "+", num2, "=", add(num1, num2))

elif choice == '2':
    print(num1, "-", num2, "=", subtract(num1, num2))

elif choice == '3':
    print(num1, "*", num2, "=", multiply(num1, num2))

elif choice == '4':
    print(num1, "/", num2, "=", divide(num1, num2))

else:
    print("Invalid input")

In this program, we define four functions to perform the basic arithmetic operations: add(), subtract(), multiply(), and divide(). Each function takes two numbers as input and returns the result of the corresponding operation.

We then get input from the user to select an operation and enter two numbers. We use the input() function to get the user's choice of operation and store it in the choice variable. We also use the float() function to convert the user's input of numbers from string to float.

Finally, we use an if statement to perform the selected operation and print out the result using the corresponding function. If the user enters an invalid choice, we print out an error message.