Welcome to today's session, where we are embarking on a journey into the mystical territory of combined string and array operations. Have you ever thought about how to update a string and an array in parallel while a specific condition holds true? That's precisely what we'll explore today, all in the context of a real-world scenario related to a mystery novel book club. Get ready to dive in!

Our mission for today is to generate a unique encoded message for a book club. Here's the fun part: to create a cryptic message, we will process a string and an array of numbers simultaneously and stop once a given condition is satisfied.

For the string, our task is to replace each letter with the next alphabetical letter and then reverse the entire updated string. For the array of numbers, our task is to divide each number by 2, round the result, and accumulate the rounded numbers until their total exceeds 20.

When the accumulated total exceeds 20, we immediately stop the process and return the updated string and the as yet unprocessed numbers in their original order.

Example

Consider the input string "books" and array [10, 20, 30, 50, 100].

We start our process with an empty string and a sum of 0.

• For the first character 'b' in 'books', we replace it with the next alphabet 'c'. For the corresponding number 10 in the array, we divide it by 2 and round it. The result is 5. The sum after first operation is 5 which is less than 20, so we continue to the next character.
• For the next character 'o', we replace it with 'p'. And for the corresponding number 20 in the array, half and rounded is 10. The sum after the second operation is 15 (5 + 10). The sum still doesn't exceed 20, so we move to third character.
• For the next character 'o', we replace it with 'p'. And for the corresponding number 30 in the array, half and rounded is 15. When we add this '15' to our previously calculated sum 15, it totals to 30 which is more than 20. So, we stop the process here.