Normally a clue will not be enough to complete a line, but every time you add a dot or solid to a square, you are adding it to both a column and a row - this extra piece of information may change a previously impossible line into one you can now solve. Thus by moving around the puzzle and solving bits here and there you can gradually complete the picture.

The following examples consider one row at a time. The top line illustrates it how it is when you start thinking about it, the middle lines (if any) show the reasoning, and the bottom line shows it solved, as far as it can be with the information given. The same reasoning is applied to both rows and columns.

If there are any lines with a single 0 clue fill the whole line with dots
If there are any lines with a single number equal to the line length fill the whole line with solids.
You can complete any line if the clues plus the minimum one dot between each of them equals the length of the line. In this case 2+1+3+1+3 equals the line length.
If your clue is larger than half the available space see how far it could reach from either end. You know that the squares that overlap must be solids.
Here treat the 2 & 4 as though they are a single unit separated by the minimum one dot. Imagine it at either end of the gap and see if any block of solids always covers any square(s), if so you can fill them. (Notice that you cannot fill the squares that are overlapped by different blocks because the space that separates them might be there somewhere).
If you have used the above techniques you will have made some inroads into solving a Griddler puzzle. The following examples are based on the assumption that you have managed to fill in some of the squares in a row or column as a result of working on other rows or columns.
This line already has a dot in it. You can use the above techniques in the gaps. In this case you can see that only one available gap is big enough for your clue and you can part fill it with solids. In this case you can also fill the smaller gap with dots.
This line is part filled with two solids. You know they must be part of the single clue. You do not know where to put the solids but you can fill in some dots where the solids cannot reach.
These techniques can be used with several blocks of solids. Imagine them as a single piece, which you can slide along up and down the line. If some squares always appear as either dots or solids you can fill them. Look for gaps in part filled lines and see what might fit and what cannot fit, always ensuring that you do not contradict the clues.

Remember that the only question is how many dots there are before and after each block of solids!
Happy Griddling.




Six Sunday Telegraph Books of Griddlers are currently available from Telegraph Books Direct (phone 0870-155-7222) or from any good bookshop.

Back to Griddler
Griddler"TM is the Registered Trademark of Telegraph Group 1998 and Nonogram"TM is the Registered Trademark of James Dalgety 1995

Text & Images Copyright 2002 James Dalgety / The Sunday Telegraph / PAN Macmillan Books. (Most recent revision 15 November 2002)