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<html><body>var_dump(checkdate(12,31,-400));echo "<br>";var_dump(checkdate(2,29,2003));echo "<br>";var_dump(checkdate(2,29,2004));</body></html><html><body>var_dump(checkdate(12,31,-400));echo "<br>";var_dump(checkdate(2,29,2003));echo "<br>";var_dump(checkdate(2,29,2004));</body></html>