Rules and how to solve Slitherlink.
Rules
  1. Decide whether to draw a line segment on each side of the cell surrounded by four points to meet the following conditions.
  2. The number specified in the problem represents the number of sides on which a line is drawn out of the four sides of this cell surrounded by four points.
  3. Line segments do not branch or cross on the way.
  4. The connection of line segments becomes one loop. It must not break off a loop, or form two loops.


jump to slilin problem.
Tips for solving
スリザーリンクの基本は ある辺に線を引くとどこかで問題数字指定の本数の線が引けなくなれば 元の辺には線を引かない、 逆にある辺に線を引かないとどこかで問題数字指定の本数の線が引けなくなれば 元の辺には線をくことです。 しかし毎回このように考えていたら大変です。ある数字の配置の時には上の基本に戻って考えると線の引き方が決まるパターンがいろいろあります。 このパターンを見つけて覚えておくと解くのがスムーズになります。
最初はこの特定の数字が並んだところ、特定の数字が特定の場所にあるところに注目です。二つの数字が縦・横・斜めに並んでいるところでは線分が引けるところが決まるものがあります。
隅や辺でも特定パターンがあります。
The basics of Slitherlink are: If you draw a line on a certain side, and if the number of lines specified by the problem number cannot be drawn somewhere, then do not draw a line on the original side.Conversely, if you do not draw a line on a certain side, and if the number of lines specified by the problem number cannot be drawn somewhere, then draw a line on the original side .
However, it is difficult if you think like this every time. There are various patterns that determine how to draw a line when you return to the basics above when arranging a certain number. Finding and remembering this pattern will make it easier to solve.
At first, notice that this particular number is in a row, and that the particular number is in a particular place. Where two numbers are lined up vertically, horizontally, or diagonally, there are things that determine where a line segment can be drawn.
There are specific patterns in the corners and sides.
See the following figure. Where 3 is arranged diagonally, where 0 and 3 are arranged vertically (or horizontally), etc., the places where line segments can be drawn are determined as shown in the figure.Naturally, line segments can not be drawn on the four sides of the cell where 0 is specified, so it is better to put a mark × for prohibiting line segments.
You don't need to mark × as you get used to it, as it is a reminder.
In some of the patterns in the following figure, try to make the line where the line is drawn banned, or try to make the line banned where the line is drawn, then there will certainly be some inconsistency.
It is also a practice to find your own pattern.
ex0
Pay attention to the area where the line is fixed or prohibition is confirmed , and make sure that does not have two loops. Or draw a line while thinking about how to draw a line so that it does not break , and decide where to prohibit.
If you get stuck in one place, it's better to consider another place than to worry too much.
Let's consider the actual problem.
The following figure is the problem. First, look for a fixed sequence of numbers.
ex1
There are 3s diagonally conectted in left upper area and is arranged diagonally, 0,3 connected in lower right area, about these cells line segments can be drawn are determined as shown in the following figure.
At the same time, mark line prohibition around 0.
ex2
Now look at the red × at the bottom right of the 0.Here, if you draw a line segment, it will be interrupted, so line segments are prohibited. If a line segment is prohibited here, a line segment cannot be drawn at the lower left, so it is prohibited.Then you can draw the green line segment.
Even in the upper part of the center, no line segment can be drawn at the two places marked with red ×, so the line marked with a green × are also prohibited.
If you draw a red line segment at the upper left daiagonally arranged 3 , it will be decided as a yellow line segment and there will be multiple loops of line segments, so this red line segment can not be drawn (prohibited).
ex3
Where the upper left 3 is arranged diagonally, a green line segment is fixed as shown in the following figure.
The blue line segment is also confirmed at the lower right 3.
Considering 2 in the lower left corner, there are only two ways to draw two line segments around the cell in this corner: two red line segments or two yellow line segments. But if you draw a yellow line segment, you will not be able to draw three line segments around the cell 3 on the upper right of 2, so you can see here that only red line segments can be drawn.
The red prohibition × around the upper right where 0 and 1 are arranged diagonally is also determined.
ex4
When the two lines of the lower left cell 2 are determined, a green line can be drawn as shown in the following figure.
Next, the area around the cell 3 can be confirmed with a blue line segments and a blue × mark.
ex5
Next, a green line segment is determined as shown in the following figure. ex6
As shown in the following figure, when the blue line segment can be drawn, the circumference of the cell 1 is also determined.
At the end, draw the lines so that they do not form two loops, and the connection is completed.
ex7
The following figure is the correct solution.
( x marks are remarks. If the line segment positions are the same, it is correct.)
There are various ways to learn, so if you think and wear them, you will be able to solve difficult problems.
ex8
Next, I will introduce some patterns. Thinking about why this would be a good exercise.
The arrangement of blue 020 in the upper left of the following figure determines the blue line.
A yellow line is determined by the yellow 02 placed on the upper side of the problem.
The red 313 located on the right side of the problem determines the red lines.
The gray line is determined by the black 23 located in the lower left corner of the problem.
The purple line is determined by the purple 332 at the lower right.
If the green line segment and × are fixed around green 3,2 cells at the center, light green lines will be decided.

There are many other ways to do this.
ex10



2020.2.28 Modified
2010.6.12 First edition
Jump to top of Karino's HomePage.

mail to T.Karino