| a | b | c | d | e | f | g | h | i | |
| A | 3 | 4 | |||||||
| B | 3 | 1 | 9 | ||||||
| C | 5 | 9 | 6 | 8 | |||||
| D | 6 | 9 | 4 | 8 | |||||
| E | |||||||||
| F | 7 | 4 | 3 | 9 | |||||
| G | 9 | 4 | 8 | 2 | |||||
| H | 6 | 8 | 1 | ||||||
| I | 1 | 7 |
So first look for 1s by columns. The first three columns only have one 1 so nothing can be done.
Running. Press the Stop button to pause the tutorial. Help page.