1024. Sum The Strings

Create a function that takes 2 integers in form of a string as an input, and outputs the sum (also as a string):

Example: (Input1, Input2 -->Output)

"4",  "5" --> "9"
"34", "5" --> "39"
"", "" --> "0"
"2", "" --> "2"
"-5", "3" --> "-2"

Notes:

• If either input is an empty string, consider it as zero.

• Inputs and the expected output will never exceed the signed 32-bit integer limit (2^31 - 1)

Solution:

def sum_str(a, b):
    return f"{sum(map(_int, [a, b]))}"

def _int(s: str):
    return int(s or 0)