I. Quantity

First of all, we define several nouns in a unified way to facilitate the communication in the solution of the ring. Please look at the picture below, the left is the left, the left hand holds it, the right hand is the right hand, and the right hand is free to operate! From left to right, we number each ring as 9, 8, 7, 6, 5, 4, 3, 2, 1.

Second, the ring is broken.

1, then enter the specific operation of solving the nine chains, and I will write it out step by step to facilitate repeated learning and practice: 1 The ring turns from the upper right to the left to form a false eight chain; The third ring winds down from the upper right to the left; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound from top right to left, forming a pseudo six-ring chain.

2. The five rings are wound from the upper right to the lower left; 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; Turn right on the third ring road and turn down; Turn right on the 1 ring and then turn down. Step 10: 1 and ring 2 are simultaneously wound. The fourth ring winds down from the upper right to the left; 1 and 2 rings go up and down at the same time; 1 ring rotates up and down; The third ring winds down from the upper right to the left; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound. Form a pseudo-four ring.

3, (1), the seventh ring around the top; 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; Turn right on the third ring road and turn down; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound; Turn right on the fourth ring road and turn down; 1 and ring 2 go up and turn right at the same time; 1 The ring rotates up and down.

(2) The third ring turns from the upper right to the lower left; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound; On the Fifth Ring Road, turn right and turn down; 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; Turn right on the third ring road and turn down; On the 1 ring, it winds down to the right to form a 98-empty six-ring chain.

4. Ring 1 and 2 are simultaneously wound; The third ring winds down from the upper right to the left; 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; The third ring winds down from the upper right to the left; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound; The sixth ring turns from the top right to the left, forming a single five-ring with 98 spaces.

5. 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; Turn right on the third ring road and turn down; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound; Turn right on the fourth ring road and turn down; At the same time, 1 and 2 cycle up and down to the right, forming 98 empty five links.

6. The1ring winds down from the top right to the left; The third ring winds down from the upper right to the left; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound; The five rings meander from the upper right to the left; A single tetracyclic ring is formed in 98 vacancies. 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; Turn right on the third ring road and turn down; 1 Turn right on the ring and turn down; Form a 98-empty four-ring chain.

7. Ring 1 and 2 are simultaneously wound; The fourth ring winds down from the upper right to the left; 1 and ring 2 go up and turn right at the same time; 1 ring rotates up and down; The third ring winds down from the upper right to the left; 1 Turn right on the ring and turn down; 1 and 2 rings are simultaneously wound from top right to left to form a single 98 ring; Step 065: The ninth ring turns from the upper right to the lower left to form a single eight-ring.

Until this step, we successfully untied the first link in the nine-ring chain. In other words, the real solution of the next ring is when the ninth ring of our number is solved from the cross frame. The next step is to restore to the eighth ring and then solve the second ring. And so on, until the nine rings are separated from the cross frame, it is the last broken ring.

Nine-chain principle:

1, Rubik's cube principle

The design of the nine-ring chain was inspired by the Rubik's Cube. By moving the position of the ring, the state of the adjacent ring can be changed. The difficulty of nine rings lies in finding the correct moving order and method.

2. Topology principle

Topology is a branch of mathematics that studies spatial form and deformation. Nine chains are essentially a topological problem, and each ring is a torus, forming a topological space with each other.

3. The principle of group theory

The solution of nine chains can be explained by group theory. Moving the ring every time is equivalent to performing an operation, and all possible operations are grouped together. If we find the nature of the group, we can find the law of solving the problem.