# What are nonogram puzzles

## Nonograms

Even if you know the nonogram rules, every beginning is difficult. Here we show you the most important techniques to successfully solve nonograms.

### Shifting technology (1)

(a)

It is not known exactly where the block of 7 in Figure (a) is, but there are some boxes that are definitely black. How do you find them? Place the block in your mind (or with the help of counting arrows, see below) as far to the left as possible and as far to the right as possible. In any case, there is part of the block where the two extreme cases intersect, and we can paint the corresponding boxes black. When playing nonograms on paper, you usually make light markings as you count the boxes on either side. With the counting mode and the blue counting arrows in our "Let's IQ Nonogram" app, this is also possible on the screen!

(b)

On the other hand, if there is no overlap as with the block of 4 in figure (b), no boxes can be colored.

### Shifting technology (2)

(c)

The shift technique can of course also be used if there is more than one block in the relevant row or column, see Figure (c). Again you place the blocks in your mind (or with the help of the counting arrows) as far to the left as possible. It is important to remember that at least one square must be free between two blocks of the same color. Then you place the blocks as far to the right as possible. Where there is overlap same Blocks there, the boxes can be colored.

### Shifting technology (3)

(d)

If, as in figure (d), boxes have already been determined, these can be taken into account in the mental shift in order to possibly achieve even more overlap. In our example, this means in concrete terms: The block of 2 cannot be placed further to the left because the box has already been marked as free. In the opposite direction, the block of 4 cannot be positioned further to the right than shown. This results in more overlap than in the previous example.

### Shifting technology (4)

(e)

Since there does not necessarily have to be a free box between two differently colored blocks in the case of colored nonograms, the counting arrows belonging to different colors are generally lined up without a gap (this is shown in example (e) when counting from left to right).
In the case of colored nonograms, however, additional information can be obtained: If you look at a line, the numerical information from the columns (and also the boxes already entered in the columns) can provide important information. (Similarly, when looking at a column, information can also be obtained from the rows.)
In our specific example, there should only be a black block of 7 in the 6th column. This tells us that the red block of 4 of the row under consideration cannot hit the 6th column. The extreme positioning of the block of 4 is thus three boxes further to the left than without this additional information.

### Further examples

(f)

The first box in the line in example (f) cannot be black, because the first block should be a block of 2, which can only be placed to the right of it due to the box that has already been marked as free. The first box must therefore be free.

(G)

The box between the fields marked in black in example (g) cannot be black because there is no block with three or more boxes in the line. So we mark it as free.

(H)

The black box in figure (h) clearly belongs to the block of 4 and not to the block of 1. (Because to the left of it no block of 4 plus an intermediate box could be placed.) If you mentally arrange the block of 4 as far to the left as possible, the first box in the line remains empty. We therefore mark it as such.

(i)

The existing black box in example (i) clearly belongs to the block of 3. This determines its position exactly and we can also paint the two other boxes in black. We close the block of 3 with a free box.

(j)

The black, already existing box from example (j) certainly belongs to the block of 4. If you move the block in your mind, the box to the right of the existing one is always black because you couldn't place the block of 4 any further to the left.

### Techniques for colored nonograms

The colored nonograms have already been discussed in Figure (e). Here are three more examples that show specific situations with colored nonograms.

 (k) A black block of 1 should be placed in the first line. Since there are only red blocks in columns 4 and 5, the intersection points must be free. In column 2 there is a black block of 2, but above it there should be a red block of 1. Therefore the box in row 1 / column 2 must be free. →
 (l) In all lines - with the exception of line 2 - a black block is provided first. Therefore the red block of 1 from column 1 can only be placed in row 2. →
 (m) The red block has already been placed in column 3. That means, only the black block is missing there. Therefore, the third box in line 2 cannot be red and must therefore be empty. →

In addition to the solution techniques presented here, there are of course many more. You will surely find out for yourself in the course of time. Have lots of fun with it!