------------------------------------------------------ Perfect Shuffle Visualization ------------------------------------------------------ How many times does it requires for 15 cards to go back to where one started? inspired by: http://d.hatena.ne.jp/nishiohirokazu/20100107/1262835414 ------------------------------------------------------------ The Perfect Shuffle resets order when ... cards = (1<<(n>>1))-((n&1)<<1); steps = (n&~1)>>(n&1); Press left or right arrow to change the n value. ------------------------------------------------------------ webpage; http://soundimpulse.sakura.ne.jp/perfect-shuffle/