February 25, 2016 10:55 · Feb 25, 2016
diff --git a/CategoryRepository.php b/CategoryRepository.php
@@ -0,0 +1,23 @@
+function buildTree($data, $parentID = 0) {
+
+        // build a tree using references and not recursion
+        $references = array();
+        $tree = array();
+
+        foreach ($data as $id=> &$node) {
+            // Use id as key to make a references to the tree and initialize it with node reference.
+            $references[$node['id']] = &$node;
+
+            // Add empty array to hold the children/subcategories
+            $node['children'] = array();
+
+            // Get your root node and add this directly to the tree
+            if ($node['parentID']==$parentID) {
+                $tree[$node['id']] = &$node;
+            } else {
+                // Add the non-root node to its parent's references
+                $references[$node['parentID']]['children'][$node['id']] = &$node;
+            }
+        }
+        return $tree;
+    }