Untie the nine chains * * *, it takes 256 steps, as long as the next ring is installed, even if it is a step, it is not sliding on the frame. The solution of nine chains is a pair of inverse processes, and the solution is the same as the gray code of the computer.

The rings of the nine-ring chain restrict each other, and only the first ring can go up and down freely. In order to get down/up the nth ring, two conditions must be met (except the first ring). 1.n- 1 ring on the rack; 2. None of the rings in front of the n-1ring are on the shelf.

When playing, all nine rings are connected to the copper ring according to law, or all of them are untied after putting on sleeves. Its solutions are diverse, separable and changeable. The winner needs 8/kloc-0 times to arrange nine connected rings in a row, and then it takes another time to untie all nine rings.

Extended data:

history

1. In the west, before16th century, nine chains were recorded in Europe.

2. In the mathematical literature published in Paris from 65438 to 0550, this "China problem" was explicitly discussed. Cardin, a famous Italian mathematician, called it "China's Nine Rings" in his works.

3. 1685, British mathematician Varis gave a detailed mathematical explanation. /kloc-In the 9th century, Gross gave it a very beautiful answer with binary numbers.

References:

Baidu Encyclopedia-Jiuhuan