Xcode stops working while trying to run the code

Hi there, I am new around here and still learning. I am working on a challenge project which is supposed ask user questions from times table. Everything was okay but suddenly Xcode stops working whenever i want to run the code. I changed literally nothing. Just took 10 minutes of break and came back and nothing works. I can't resume previews and can't run on simulator. I tried to clean build, relaunch xcode and even restart my computer but nothing solves my problem.

I would be appreciated if someone can enlighten me.

I figured it out. Sorry for wasting your time.

Glad to hear that. Care to share what the fix was?

Xcode stops working while trying to run the code
 
 
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