1  1  2  4
  3  1  3  1
 AJ  3 BJ  2
  3  2  4  2
===============
  1  1  2  4
  3  1  3  1
  0  3 BJ  2
 A3  2  4  2
===============
  1  1  2  4
  3  1  3  1
  0  3  0  2
 A3  2 B4  2
===============
  1  1  2  4
  3  1  3 A1
  0  3  0  2
  0  2 B4  2
===============
  1  1  2  4
  3  1  3 A1
  0  3  0 B2
  0  2  0  2
===============
  1  1  2 A4
  3  1  3  0
  0  3  0 B2
  0  2  0  2
===============