3
9
5
7
4
2
4
6
3
1
6
1
4
5
4
5
2
1
9
6
3
8
6
8
7
2
3
4
8
4
9
3
6
3
2
5
2
1
8
5
6
9
remove
switch
1
2
3
4
5
6
7
8
9
clear highlight
clear board
reset game
new game
difficulty: very easy