Extended Bi-value Oddagon

[SunnieShine]

标题：拓展死环

About 10 o'clock, my friend found that a strange post, whose topic is about the introduction of a structure (pattern) in a BBS, then he re-posted to me.

大概 10 点钟的样子，我朋友在一个论坛上发现了一个介绍奇怪的结构的帖子，然后它就把帖子转给我看了。

The pattern is like this:

这个结构大概长这样：

He said, regardless of the removal of all digit 3, digit 4 or digit 5 in this pattern, the pattern will be dead. Therefore, we can conclude that the all peer intersections from the digit 3, 4 and 5 can be eliminated.

他说，不管我们移除所有结构里的 3、4 或者 5 的哪一个数字，结构都会直接挂掉。所以，我们可以下结论认为所有 3、4、5 的全部能看到的地方，全都可以删除。

As the picture above, the candidate 5r5c9 and 4r9c5 can be eliminated safely.

如图所示，r5c9(5) 和 r9c5(4) 是可以删除的。

Extended consideration

标题：更多的考虑

Such as that pattern, because this pattern is extended from a bi-value oddagon, so we can think that this pattern is named a extended bi-value oddagon.

比如这个结构，因为这个结构从一个死环拓展起来，所以我们可以认为这个技巧叫做“拓展死环”。

If we can summary up an abstract pattern, the technique may be very useful.

如果我们能总结出一个抽象结构出来的话，那么这个技巧可能就会很有用。