有一个点在19*19的平面上运动,运动轨迹为

一共移动了90步,顺序为
| y | x | y | x | y | x | |||||
| 0 | 17 | 16 | 30 | 10 | 8 | 60 | 15 | 15 | ||
| 1 | 3 | 6 | 31 | 10 | 7 | 61 | 14 | 15 | ||
| 2 | 12 | 17 | 32 | 9 | 9 | 62 | 16 | 15 | ||
| 3 | 4 | 12 | 33 | 10 | 9 | 63 | 18 | 15 | ||
| 4 | 3 | 18 | 34 | 15 | 12 | 64 | 17 | 15 | ||
| 5 | 5 | 18 | 35 | 16 | 12 | 65 | 18 | 17 | ||
| 6 | 7 | 16 | 36 | 17 | 12 | 66 | 19 | 16 | ||
| 7 | 8 | 16 | 37 | 13 | 9 | 67 | 14 | 18 | ||
| 8 | 6 | 12 | 38 | 17 | 6 | 68 | 14 | 17 | ||
| 9 | 9 | 16 | 39 | 13 | 4 | 69 | 12 | 3 | ||
| 10 | 8 | 11 | 40 | 16 | 7 | 70 | 19 | 11 | ||
| 11 | 5 | 12 | 41 | 18 | 6 | 71 | 12 | 15 | ||
| 12 | 7 | 11 | 42 | 14 | 5 | 72 | 8 | 8 | ||
| 13 | 5 | 14 | 43 | 16 | 5 | 73 | 18 | 4 | ||
| 14 | 3 | 10 | 44 | 12 | 4 | 74 | 17 | 2 | ||
| 15 | 4 | 10 | 45 | 18 | 11 | 75 | 18 | 3 | ||
| 16 | 5 | 10 | 46 | 2 | 10 | 76 | 17 | 4 | ||
| 17 | 6 | 9 | 47 | 6 | 13 | 77 | 16 | 3 | ||
| 18 | 9 | 12 | 48 | 4 | 14 | 78 | 11 | 5 | ||
| 19 | 6 | 8 | 49 | 10 | 16 | 79 | 10 | 2 | ||
| 20 | 2 | 13 | 50 | 12 | 16 | 80 | 2 | 16 | ||
| 21 | 9 | 11 | 51 | 11 | 15 | 81 | 6 | 19 | ||
| 22 | 11 | 11 | 52 | 12 | 18 | 82 | 9 | 1 | ||
| 23 | 2 | 15 | 53 | 9 | 18 | 83 | 10 | 1 | ||
| 24 | 13 | 12 | 54 | 6 | 16 | 84 | 9 | 7 | ||
| 25 | 2 | 14 | 55 | 8 | 17 | 85 | 11 | 6 | ||
| 26 | 3 | 12 | 56 | 12 | 2 | 86 | 3 | 13 | ||
| 27 | 14 | 12 | 57 | 7 | 18 | 87 | 12 | 1 | ||
| 28 | 12 | 12 | 58 | 15 | 16 | 88 | 13 | 16 | ||
| 29 | 10 | 10 | 59 | 17 | 11 | 89 | 8 | 7 |
由计算

按照运动位置不可重复统计3点结构占比
| 1 | 2 | 3 | 4 | 5 | 6 | |
| 蓝 | 3 | 6 | 25 | 14 | 39 | 1 |
| 红 | 8 | 3 | 20 | 16 | 40 | 0 |

两条曲线差别很小,这里把蓝色的数据3,6,25,14,39,1当作常数。用2a1+1的方式预测第3个点的可能结构。
如蓝色前两个点(0,1)为2a2

8(2a2+1)=3a1+2*3a3+2*3a4+3*3a5

2a2+1可以得到4种3点结构,因为在3,6,25,14,39,1种3a5占比最大,因此2a2+1取3a5.因此前3个点的结构预测是3a5,前3个点(0,1,2)为

组成的结构就是3a5.
再用(1,2)预测第4个点的运动方式

这个结构也是2a2,所以预测(1,2,3)的结构也是3a5.

结构(1,2,3)就是3a5.
5(2a1+1)=3a1+3*3a2+3a3

如果前2个点是2a1,第3个点的运动方式就取3a3.
5(2a3+1)=3a1+3a4+3*3a6

如果前2个点的分布是2a3,就预测第3个点的运动方式为3a4.
用这种方法预测所有2-89步
| 预测 | 真实 | 预测 | 真实 | 预测 | 真实 | ||||||||||||||
| 2 | 5 | 5 | 1 | 32 | 4 | 4 | 1 | 62 | 3 | 2 | 0 | ||||||||
| 3 | 5 | 5 | 1 | 33 | 5 | 1 | 0 | 63 | 3 | 2 | 0 | ||||||||
| 4 | 5 | 5 | 1 | 34 | 3 | 3 | 1 | 64 | 3 | 2 | 0 | ||||||||
| 5 | 5 | 3 | 0 | 35 | 5 | 3 | 0 | 65 | 3 | 1 | 0 | ||||||||
| 6 | 3 | 3 | 1 | 36 | 3 | 2 | 0 | 66 | 5 | 5 | 1 | ||||||||
| 7 | 5 | 3 | 0 | 37 | 3 | 3 | 1 | 67 | 5 | 5 | 1 | ||||||||
| 8 | 3 | 3 | 1 | 38 | 5 | 4 | 0 | 68 | 5 | 4 | 0 | ||||||||
| 9 | 5 | 3 | 0 | 39 | 5 | 4 | 0 | 69 | 4 | 4 | 1 | ||||||||
| 10 | 5 | 5 | 1 | 40 | 5 | 5 | 1 | 70 | 5 | 5 | 1 | ||||||||
| 11 | 5 | 5 | 1 | 41 | 5 | 5 | 1 | 71 | 5 | 4 | 0 | ||||||||
| 12 | 5 | 3 | 0 | 42 | 5 | 5 | 1 | 72 | 5 | 5 | 1 | ||||||||
| 13 | 5 | 4 | 0 | 43 | 5 | 3 | 0 | 73 | 5 | 5 | 1 | ||||||||
| 14 | 5 | 5 | 1 | 44 | 3 | 3 | 1 | 74 | 5 | 5 | 1 | ||||||||
| 15 | 5 | 3 | 0 | 45 | 5 | 5 | 1 | 75 | 5 | 4 | 0 | ||||||||
| 16 | 3 | 2 | 0 | 46 | 5 | 5 | 1 | 76 | 5 | 4 | 0 | ||||||||
| 17 | 3 | 3 | 1 | 47 | 5 | 5 | 1 | 77 | 5 | 3 | 0 | ||||||||
| 18 | 5 | 5 | 1 | 48 | 5 | 5 | 1 | 78 | 5 | 5 | 1 | ||||||||
| 19 | 5 | 4 | 0 | 49 | 5 | 5 | 1 | 79 | 5 | 5 | 1 | ||||||||
| 20 | 5 | 5 | 1 | 50 | 5 | 3 | 0 | 80 | 5 | 5 | 1 | ||||||||
| 21 | 5 | 5 | 1 | 51 | 3 | 3 | 1 | 81 | 5 | 5 | 1 | ||||||||
| 22 | 5 | 3 | 0 | 52 | 5 | 4 | 0 | 82 | 5 | 5 | 1 | ||||||||
| 23 | 3 | 3 | 1 | 53 | 5 | 3 | 0 | 83 | 5 | 3 | 0 | ||||||||
| 24 | 5 | 5 | 1 | 54 | 3 | 3 | 1 | 84 | 3 | 1 | 0 | ||||||||
| 25 | 5 | 4 | 0 | 55 | 5 | 5 | 1 | 85 | 5 | 5 | 1 | ||||||||
| 26 | 5 | 3 | 0 | 56 | 5 | 5 | 1 | 86 | 5 | 5 | 1 | ||||||||
| 27 | 5 | 3 | 0 | 57 | 5 | 5 | 1 | 87 | 5 | 5 | 1 | ||||||||
| 28 | 3 | 2 | 0 | 58 | 5 | 5 | 1 | 88 | 5 | 5 | 1 | ||||||||
| 29 | 3 | 3 | 1 | 59 | 5 | 5 | 1 | 89 | 5 | 5 | 1 | ||||||||
| 30 | 5 | 4 | 0 | 60 | 5 | 4 | 0 | ||||||||||||
| 31 | 4 | 6 | 0 | 61 | 5 | 3 | 0 |
有51组正确,正确率57.9%。
也就是从第3步开始,可以有57.9%的概率知道蓝点可能的运动方式。