SUPyF2 P.-Mid-Exam/30 June 2019/1 - Number Array

"""
Programming Fundamentals Mid Exam - 30 June 2019 Group 1
Check your code: https://judge.softuni.bg/Contests/Practice/Index/1682#1

SUPyF2 P.-Mid-Exam/30 June 2019/1 - Number Array

Problem:
Create a program that helps you keep track of a number array.
First, you are going to receive the numbers оn a single line, separated by space, in the following format:
"{number1} {number2} {number3}… {numbern}"
Then you will start receiving commands until you read the "End" message. There are five possible commands:
• "Switch {index}"
o   Find the number on this index in your collection, if the index exists, and switch its sign (negative <-> positive).
• "Change {index} {value}"
o   Replace the number on the given index with the number given, if the index exists.
• "Sum Negative"
o   Print the sum of all negative numbers.
• "Sum Positive"
o   Print the sum of all positive numbers.
• "Sum All"
o   Print the sum of all numbers.
In the end, print the positive numbers on a single line, keeping in mind that 0 is positive,
separated by a single space in the following format:
"{number1} {number2} {number3}… {numbern}"
Input
• On the 1st line you are going to receive the numbers of the array (always integers), separated by a single space.
• On the next lines, until the "End" command is received, you will be receiving commands.
Output
• Print the tasks in the format described above.

Examples:
Input:              Output:
1 2 3 4 5           -8
Switch 4            2 3 4
Change 0 -3
Sum Negative
End

Comments:
First, we receive the command "Switch 4" and we make the number on index 4 negative
(because it is positive before the command). After this command, the task collection looks like this:
1 2 3 4 -5
Afterwards, we receive the "Change 0 -3" command and we need to change the number on index 0 with the number -3.
The collection looks like this now:
-3 2 3 4 -5
After that, we receive the "Sum Negative" command,
which means we need to print the sum of all negative numbers and it is -8.
In the end, we print all of the positive numbers. This is the result collection:
2 3 4

Input:                      Output:
1 2 3 4 5 4 3 2 1 0         23
Switch -4                   2 3 4 5 4 3 2 1 0
Change 13 0
Switch 0
Sum All
End
"""
nums = [int(num) for num in input().split()]

while True:
    command = input().split()
    if command[0] == "End":
        print(' '.join([str(num) for num in nums if num >= 0]))
        break

    elif command[0] == "Switch":
        index = int(command[1])
        if 0 <= index < len(nums):
            nums[index] = nums[index].__invert__() + 1

    elif command[0] == "Change":
        index, value = int(command[1]), int(command[2])
        if 0 <= index < len(nums):
            nums[index] = value

    elif command[0] == "Sum":
        if command[1] == "Negative":
            print(sum([num for num in nums if num < 0]))

        elif command[1] == "Positive":
            print(sum([num for num in nums if num >= 0]))

        elif command[1] == "All":
            print(sum(nums))