solve(ANS,12).
choice2([3,14,6,9], [ ], ANS, 0, 12)
choice2([14,6,9], [0], ANS, 0, 12)
choice2([6,9], [0,0], ANS, 0, 12)
choice2([9], [0,0,0], ANS, 0, 12)
choice2([9],[6,0,0],ANS,6,12)
H=6,T=[9],L=[0,0],
X=0,SUM=12
Y=6,Y=<12
choice2([ ],[0,6,0,0],ANS,6,12)
SUM=6,SUM=12 不一致
(失敗)
Y=<12を
充足しない
(失敗)
H=9,T=[],L=[6,0,0],
X=6,SUM=12
Y=15