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<?php $source=json_decode('[{"parentTitle":"Winner 2009","catTitle":"Mas Muster","title":"drm202"},{"parentTitle":"Winner 2009","catTitle":"Mas Muster","title":"drm202"},{"parentTitle":"Winner 2011","catTitle":"Josh Frank","title":"A bird in the cage"},{"parentTitle":"Winner 2011","catTitle":"Josh Frank","title":"cue & repeat"}]'); $result=array(); array_walk($source,function($v,$i)use(&$result){ if(!isset($result[$v->parentTitle])) $result[$v->parentTitle]=array(); if(!isset($result[$v->parentTitle][$v->catTitle])) $result[$v->parentTitle][$v->catTitle]=array(); if(!in_array($v->title,$result[$v->parentTitle][$v->catTitle])) $result[$v->parentTitle][$v->catTitle][]=$v->title; }); print_r($result); // just to debug echo "<ul>"; foreach($result as $key=>$sub){ echo "<li>".htmlentities($key,ENT_COMPAT,"UTF-8"); echo "\n<ul>"; foreach($sub as $k=>$s){ echo "<li>".htmlentities($k,ENT_COMPAT,"UTF-8"); echo "\n<ul>"; foreach($s as $i=>$v){ echo "<li>".htmlentities($v,ENT_COMPAT,"UTF-8")."</li>\n"; } echo "</ul>\n</li>"; } echo "</ul>\n</li>"; } echo "</ul>";