alex prezmon alex prezmon - 1 month ago 19
Python Question

python addition 2 digit number

I'm studying algorithms. The exercise consist in put a number of 2 digits (between 10 and 99) and then do the addition of the two digits. I made it in python and it works, but my teacher said that there's another way to do it without the conversions that i'm using. Can you help me? Is there a better way? Thanks.

for i in range(5):
add = 0
num = input("Number: ")
num = int(num)
if num > 9 and num < 100:
num = str(num)
add = int(num[0]) + int(num[1])
print("The addition of the two digits is: " + str(add))
else:
print("It is not a two digit number.")

Answer

I think he meant:

(num // 10) + (num % 10)

With num // 10 you perform an integer division with 10. But this is the first digit. With num % 10 you get the remainder of the division, which is the second digit. For example:

>>> 67 // 10
6
>>> 67 % 10
7

The most succinct way must be:

sum(divmod(num, 10))

because divmod performs the integer division with 10 and finding the remainder at the same time. So with sum we get the sum of those two numbers. For example:

>>> divmod(67, 10)
(6, 7)
>>> sum(divmod(67, 10))
13