移動合の無駄合駒判定

[sugyan]

https://www.youtube.com/watch?v=RHXwJc0RuEA

P1 * -FU *  *  *  * -KI-UM * 
P2 *  *  * -KY *  * -KI-OU-GI
P3 *  *  *  * -GI-KE *  * -GI
P4 *  *  * -FU-KE * +GI * -KI
P5 *  * -FU-KE * -FU-KY * -KY
P6 *  * -KE * -FU * -FU *  * 
P7+HI *  *  *  *  *  * -KI * 
P8+OU+HI *  *  *  *  *  *  * 
P9+KA *  *  *  *  *  * +KY * 
P-00AL
+

   9   8   7   6   5   4   3   2   1
+---+---+---+---+---+---+---+---+---+
|   |  p|   |   |   |   |  g| +b|   | a
+---+---+---+---+---+---+---+---+---+
|   |   |   |  l|   |   |  g|  k|  s| b
+---+---+---+---+---+---+---+---+---+
|   |   |   |   |  s|  n|   |   |  s| c
+---+---+---+---+---+---+---+---+---+
|   |   |   |  p|  n|   |  S|   |  g| d
+---+---+---+---+---+---+---+---+---+
|   |   |  p|  n|   |  p|  l|   |  l| e
+---+---+---+---+---+---+---+---+---+
|   |   |  n|   |  p|   |  p|   |   | f
+---+---+---+---+---+---+---+---+---+
|  R|   |   |   |   |   |   |  g|   | g
+---+---+---+---+---+---+---+---+---+
|  K|  R|   |   |   |   |   |   |   | h
+---+---+---+---+---+---+---+---+---+
|  B|   |   |   |   |   |   |  L|   | i
+---+---+---+---+---+---+---+---+---+
Side to move: Black
Hand (Black):
Hand (White): p12
Ply: 1

["8h8g", "7f8h+", "9i8h", "6e7g", "8h7g", "5d6f", "7g6f", "4c5e", "6f5e", "5c4d", "5e4d", "3b3c", "4d3c+"]

8h8g の1手詰が正解