wap forum php code in question for help!

Made a wap forum with PHP code written.
Currently landing home when the show "Welcome, XXX" I want to welcome you into a time period divided by Good morning, good afternoon, good evening. Such a display format.
Request expert to improve the code to fill in, thank you ~
Currently code is: [Note there is a registered unregistered judgment]
if ($ groupid == $ wapnewgroupid) {
echo '<a href="index.php?action=register"> registered nickname [free] </ a>
';
} Else {
echo "Welcome, <a href=\"index.php?action=my&uid=$discuz_uid\"> $ discuz_user </ a>
';
}