What Happens When You Call A Function In It Self?

I saw an example online that looks like this:

 def DecimalToBinary(num):

      if num >= 1:
         DecimalToBinary(num // 2)
      print(num % 2, end = '')

print(DecimalToBinary(12))

I'll be happy if someone explain it to me.

It is called recursion. A type of concept of function calling itself. If it has no proper if statement that terminates the function itself, loop will not end or it will error. In your case it terminated.

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