Allow multiple cryptarithm constraints

[arnaud-m]

The different constraints are separated by a semi-colon ;.

It would allow to invent, solve, and generate cryptarithm variations.

Long Multiplication

               S E E
                  S O
             ---------
              E M O O
            M E S S
           -----------
            M I M E O

A long multiplication is stated by multiple constraints :

• SEE * SO = MIMEO
• MIMEO = EMOO + 10*MESS
• SEE * O = EMOO
• SEE * S = MESS

Note that the second constraint can not be stated yet.

• Modify the parser so that 10 is read as a number rather than a word.
• Or, define a special operator *= for the long multiplication.

Cross Number Puzzles

Modelling Cross Number Puzzles is straightforward.

ABC   *  DE = CFGH
  +      *      -
JDHJ +  DGC = JGKK
------------------
JEDK + EBAH = FAGH