**Trinairo** is a logic puzzle invented by Leo de Winter (Netherlands). The objective is to fill a **9 x 9** grid with letters so that each row and each column contains three letters **A**, three letters **B** and three letters **C**. If a cell is marked with other color, a letter in the cell differs from letters in all orthogonally adjacent cells.

**Cross+A** can solve puzzles **6 x 6**, **9 x 9** or **12 x 12**.