https://yinchi.dev/tags/puzzles/Recent content in Puzzles on Yin-Chi ChanHugo -- gohugo.ioen-usFri, 15 May 2026 00:00:00 +0000https://yinchi.dev/posts/top-spin/Fri, 15 May 2026 00:00:00 +0000https://yinchi.dev/posts/top-spin/<p><img src="top_spin.png" alt="top spin"></p> <p>In a (much) earlier <a href="https://yinchi.dev/posts/flip-puzzle/">post</a> of mine, I discussed a puzzle called <em>Top Spin</em> (once made by Binary Arts), in which 20 beads were placed on an oval track with a turntable that could flip the four beads that occupy it. I showed that it was possible to reverse the order of the beads, from <code>[1, 2, 3, ..., 19, 20]</code> to <code>[20, 19, ..., 2, 1]</code>, even if the beads were placed on a straight track instead of an oval one.</p>https://yinchi.dev/posts/flip-puzzle/Wed, 09 Jul 2025 00:00:00 +0000https://yinchi.dev/posts/flip-puzzle/<p><em>Top Spin</em> was a puzzle in which 20 beads were placed on an oval track with a turntable, such that any four consecutive beads could be flipped. Naturally, I wondered whether it was possible to reverse the order of the beads, from <code>[0, 1, ..., 19]</code> to <code>[19, 18, ..., 0]</code>.</p> <p>As it turns out, this is possible even if the beads are placed on a straight track instead of an oval one.</p>