Encoding challenge

What does this code do?

• This code defines several functions to process an encoded message stored in a text file.
• The extractNumbers function reads the file, extracts the numbers from each line, and stores them in an array.
• The rearrangeIntoStaircase function takes the extracted numbers, sorts them, and arranges them into a staircase-like structure, where each step has one more number than the previous step.
• The returnLast function extracts the last number from each step of the staircase.
• The decode function uses these extracted numbers to retrieve corresponding words from the message file and constructs a decoded message.
• Finally, the writeToFile function writes the decoded message to a new text file named "decoded.txt".

Overall, the code reads an encoded message, decodes it based on the provided numbers, and saves the decoded message to a file.