crosssum 
--------
Version 0.01
http://sourceforge.net/projects/crosssum


This is a simple game to play and design cross sum games.  
It is licensed under the GPL (see the License file).

For installation information please see the Install file.


There is one sample puzzle provided: 05166656


Here is the help:

crosssum [<filename>]

Design and play cross sum games

  ^o open an existing file
  ^s save the current board to a file
  ^r recompute the game for the board
  ^q quit
   p switch to playing mode
   v switch to verifying play mode
   d switch to designing mode

When in playing mode, you change the numbers by clicking on the
square you wish to change. The number for the square is dependent
on the position in the square that you click. Verifying play mode
is identical to play except erroneous answers are highlighted.

In desiging mode you can change a square from an answer square to
a blank square by clicking on it. One click toggles it. When you
finished designing, use ^r to compute a puzzle for the board
Squares are mirrored, if you want to override this press CTRL
while you click

The rules are:
  1. Sums must be formed from strings of [1,9] with no dups
  2. The grey squares are the answers,
     numbers above the diagonal are the answers for the sum to the right
     numbers below the diagonal are the answers for the sum below