# Additional solving techniques to diagonally symmetric Nonograms

Dear Reader: This question assumes you know what a Nonogram is. If you do not, I recommend reading the Wikipedia entry first.

Nonograms have many solving techniques. One of the lesser used ones - simply because it does not come up that often - is that if the puzzle is symmetric, you can do additional solving techniques; specifically, for a particular row - if the nonogram is vertically symmetric - the center number must be centered in the middle. Also, any solving you do on one side of the puzzle can also be immediately copied to it's reflection on the other side.

This question is about diagonally symmetric Nonograms. You can tell if a puzzle is diagonally symmetric (top left to bottom right) if the numbers on each side are the same, and symmetric top right to bottom left in the numbers are the same, but in opposite order. Here is an example of a diagonally symmetric Nonogram:

As you can see, the numbers are the same, but in reverse order, so it has top right to bottom left symmetry. Are there additional solving techniques that take advantage of this fact? How would you solve this (fairly difficult for a 10x10) puzzle?

• I think that example is only symmetric if you flip the "1, 4" clue in the fifth row to "4, 1". Feb 11 '15 at 15:21
• @Kevin I finally had time to fix the images. Had a busy day at the office :) Feb 11 '15 at 21:08