NB. 1 - The only zones accessible to the user for data entry are the" Work Area" and "Data Entry" tables
2 - There are hidden cells in rows 50 to 150 with intermediate results not useful to the user.l
Explanation of the tables:
The solution will be built in that table, adding new digits one at the time.
The displayed numbers are the sums of the corresponding cells in the nine Integer Performance Tables. They vary from 0 to a theoretical 9.
XXX is displayed in a cell with a global performance valued 0 and in which no digit has been assigned. In such case, it would be impossible to complete the grid.
The Su Doku "problem" is transcribed into that area
Integer Performance Tables.
There is an area for each digit 1 to 9. It is composed of a 9*9 individual cell performance table, a column of row totals, a row of column totals and a small 3*3 table containing the sums of the square groups..
An individual cell contains 0 if the integer cannot be placed in it (e.g. another integer is assigned to it) or 1 if it can be assigned to the it The sums of rows, columns and groups are the simple count of the ones present in the corresponding element.