Not a compiler but it seems like you are trying to make a version of repl.it More on reddit.com

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Hi OJToo, I’m the co-founder of Programiz. I think I know where the issue with the challenge is coming from, sometimes our challenge judge system behaves weirdly coz we’re simulating python input with test case data instead of actual human input, this happens especially when there’s while loops involved. The other issues you’ve mentioned are weird, our content doesn’t change much and we’ve put in a lot of effort to make the platform stable, I’ll get in touch with you tomorrow to see if there’s something we need to fix. More on reddit.com

If anyone is interested in learning how the online compiler was built, I’ve written a blog about it: https://www.programiz.com/blog/online-python-compiler-engineering/ More on reddit.com