Normal sudoku rules apply. Binairo rules apply: A run of 3 even digits never occurs in a row or column and, a run of 3 odd digits never occurs in a row or column. Each even/odd pattern must be different in the rows, and each even/odd pattern must be different in the columns. Digits increase along the thermo from the bulb. Digits separated by an X add to 10, digits separated by a V add to 5.