Is fopen not a usable function in the sololearn playground?

Question

https://code.sololearn.com/wfrWyEWu40v2/?ref=app

Answer 1

Seems that your code is deleted, please add-show your code so the community can help you more easily :)

Answer 2

Sorry about the code but i didn't mean to link it. It is irrelevant to the question, sorry.