Why In my code after I am pressed RUN button, is written "Undefined index, about $tireqty, $sparkqty and $oilqty?

Question

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https://code.sololearn.com/wD3AGDzxfho6/?ref=app

Answer 1

Thank You very much, Taste

Answer 2

because the $_POST is empty. if you run this in webserver, and call it from html form it should work