Pointer

Nodes sit on a canvas connected by next-pointers. Re-point them so traversing from HEAD produces the target order. Orphaned nodes drift away and dim; a cycle flashes its arrows red. There is also a one-click Reverse for flipping the whole chain.

• Click a node to pick up its arrow, then click another node or the NULL pad to re-point it
• The live chain from HEAD updates instantly so you can see orphans and cycles
• Solve in fewer moves and less time for a higher score

• Desktop: click a node, then click a target node or the NULL pad; click the same node again to cancel
• Phone & tablet: tap a node, then tap its new destination

• Size: 4, 6 or 8 nodes
• Daily for a shared puzzle, Practice for shuffle, reverse and build variants

• Rewire from the tail backward so you never temporarily strand the rest of the chain
• Use Reverse when the target is simply the list flipped, it is a single move instead of many

Pointer is a hands-on linked-list puzzle about pointers, orphaned nodes and cycles, making data structures visible.

• Skills: data structures, linked lists, pointers, memory
• Best for: roughly grades 9–12 (ages 14+)
• For parents & teachers: pointers and linked lists, made visible.

Nodes on a canvas joined by next-pointers, re-pointed to produce a target order, is the linked list — the data structure that stores order in the connections rather than in the positions.

Orphaned nodes drifting away and dimming is not decoration. A node nothing points to is unreachable, and in a real program it is a memory leak.

Making unreachability visible is the reason this works as teaching. A pointer is hard to learn precisely because nothing on screen normally shows the difference between an object that is gone and an object you can simply no longer name.

Pointer is a hands-on linked-list puzzle about pointers, orphaned nodes and cycles. It is an original, free browser game built in-house for PlayPendium.

A free, original browser game on PlayPendium. No download, no install.