import math
import sys

#Functions for the operations
def add(num1, num2):
    return num1 + num2

def subtract(num1, num2):
    return num1 - num2

def multiply(num1, num2):
    return num1 * num2

def divide(num1, num2):
    return num1 / num2

def expo(num1, num2):
    return num1 ** num2

#The calculating function
def calc():
    print("Select an operator:")
    print("1.Add")
    print("2.Subtract")
    print("3.Multiply")
    print("4.Divide")
    print("5.Expo")
    print("6.Root")
    select = int(input())
    if select >=1 and select <=6:
        if select == int(6):
            print("Enter a number...")
            root = int(float(input()))
            print("√", root,"=", math.sqrt(root))
        else:
            print("Enter the first number...")
            num1 = int(float(input()))
            print("Enter the second number...")
            num2 = int(float(input()))
            if select == int(1):
                print(num1, "+",num2,"=", add(num1, num2))
            elif select == int(2):
                print(num1, "-",num2,"=", subtract(num1, num2))
            elif select == int(3):
                print(num1, "*",num2,"=",  multiply(num1, num2))
            elif select == int(4):
                print(num1, "/",num2,"=", divide(num1, num2))
            elif select == int(5):
                print(num1, "**",num2,"=", expo(num1, num2))
    else:
        print("Invalid input!")


#The main function which use a while loop
def main():
    while True:
        calc()
        print('\nCalculation finished. Do another? (Y/N)')
        selector = input()
        if selector.lower() == 'n':
            break


#About the script, here I use the main function
print("This is a simple calculator on python.")
main()