Cycle through the following operations one at a time until no further operations can be performed:

1. If the string suffix is 'ac', replace it with 'cb'.
2. If the string length is greater than 15, remove the middle character.
3. If the string prefix is 'ca', replace it with 'bb' and append 'c' to the end.
4. If the string contains an even number of 'b's (and at least one 'b'), append 'ab' at the end.
5. If the string contains 'bca', delete the first occurrence entirely.
6. If the string ends with 'ca', remove the last character.

For the string "babaacaababbcabca", what is the final string after performing all operations?

Provide your answer as a string in the following format:

<<< "some_final_string" >>>
