# coding=utf-8

id = 137
group = 'trees'
number = 47
visible = True
facts = None

solution = '''\
deleteBT(X, b(nil, X, nil), nil).
deleteBT(X, b(b(Ls, E, Rs), X, R), b(L, E, R)) :-
  deleteBT(E, b(Ls, E, Rs), L).
deleteBT(X, b(L, X, b(Ls, E, Rs)), b(L, E, R)) :-
  deleteBT(E, b(Ls, E, Rs), R).
deleteBT(X, b(L, E, R), b(L1, E, R)) :-
  deleteBT(X, L, L1).
deleteBT(X, b(L, E, R), b(L, E, R1)) :-
  deleteBT(X, R, R1).
'''