斜向蜂窝 Isolated/Hex

斜向蜂窝是一种非常古老的题型。它出现在第二届世界数独锦标赛中（2007年），并且是当年赛题题集的封面。

Isolated is an antediluvian variant. It appeared in World Sudoku Championship II in 2007, and it is the cover photo of the puzzle set book.

在这个题型中，数字不能在三个方向上重复：横向，以及两个方向上的斜向。实际上，它是斜线数独的变型，我们可以将它拉直，变成正方形的斜线数独的盘面。

In this puzzle, numbers cannot repeated on 3 directions—— Row, and 2 slant direction. Actually, it is the variation of Slant, we can change it into square grids with Slant rules.