import re

def recurse(chunk,word):

    rev_string = chunk[::-1]
    rev_regex = word[::-1]

    trimmed = re.sub(rev_regex, '', rev_string)[::-1]
    # print final
    if trimmed != chunk:
        return recurse(trimmed, word)
    else:
        return trimmed


def answer(chunk, word):
    print recurse(chunk, word)
    return recurse(chunk, word)