Solution
  1 2 3 4 5 6 7 8 9  
A A
B B
C C
D D
E E
F F
G G
H H
I I
  1 2 3 4 5 6 7 8 9  
Solution
  1 2 3 4 5 6 7 8 9  
A A
B B
C C
D D
E E
F F
G G
H H
I I
  1 2 3 4 5 6 7 8 9  
loading