You are given a code:

def main_solution(x):
    return (func_13(x, '-') + func_4('axajm'))

Can you predict the output of `main_solution("mdxvacxvjc")` without writing any code? Please reason and put your final answer in the following json format: {"output": <your output>}, where <your output> should be the final string.
user
{"ref_input": {"x": "mdxvacxvjc"}, "ref_output": "m-d-x-v-a-c-x-v-j-caxajm", "ref_code": "def main_solution(x):\n    return (func_13(x, '-') + func_4('axajm'))", "funcname": "main_solution"}
rule