1. Description

Code a function calculate_checksum, which takes a series of integers as input and returns their checksum value.

The way we calculate checksum is:

• Add all the numbers
• Calculate the residual of the sum divided by 1000

For example, if the input is "123 456 789", the checksum is

2. Input & Output

Input:

• A series of integers separated by space
• Use input() as input. Notice that the value you get from input() is a string

Output:

• An integer
• Use print() for your output

Example

# Input: 
123 456 789
# Output: 
368