How to automatically typecast an int as a double here?

Question

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https://code.sololearn.com/cnuEc936tIjY/?ref=app

Answer 1

Coder Kitten Thanks! That really helps.

Answer 2

Coder Kitten Thanks for the explanation, but why in the first place does a float argument get read as a double? I tried va_arg(args, float) but it raised an error.