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<!DOCTYPE html>
<html>
<body>
    <head>
        <title>Show good morning good night wish as per time Javascript</title>
    </head>
    <script type="text/javascript">
        document.write("<center><font size=+3 style='color: green;'>");
        var day = new Date();
        var hr = day.getHours();
        if (hr >= 0 && hr < 12) {
            document.write("Good Morning!");
        } else if (hr == 12) {
            document.write("Good Noon!");
        } else if (hr >= 12 && hr <= 17) {
            document.write("Good Afternoon!");
        } else {
            document.write("Good Evening!");
        }
        document.write("</font></center>");
    </script>
</html>
</body>
</html>