Проверить является ли заданный граф блоком SWI prolog - Prolog - Ответ 8518741

blocks(GRAPH,BLOCKS,ANS):- 
    TAKE(GRAPH,D(X,Y),GRAPH1),
    findall(CYCLE,SIMPLE_CYCLE(Y,X,GRAPH,[D(X,Y)],[Y],CYCLE),CYCLES),
    COMBINE(CYCLES,[],BLOCK),
    DIFFERENCE(GRAPH1,BLOCK,GRAPH2),!,
    blocks(GRAPH2,[BLOCK|BLOCKS],ANS).
blocks([],BLOCKS,BLOCKS).
 
TAKE([D(X,Y)|GRAPH],EDGE,GRAPH):- EDGE=D(X,Y);EDGE=D(Y,X).
TAKE([ARC|GRAPH],EDGE,[ARC|GRAPH1]):- TAKE(GRAPH,EDGE,GRAPH1).
 
SIMPLE_CYCLE(Y,X,GRAPH,EDGES,TOPS,CYCLE):- Y\=X,
    TAKE(GRAPH,D(Y,Z),GRAPH1),not(MEMBER(Z,TOPS)),
    SIMPLE_CYCLE(Z,X,GRAPH1,[D(Y,Z)|EDGES],[Z|TOPS],CYCLE).
SIMPLE_CYCLE(X,X,_,CYCLE,_,CYCLE).
 
COMBINE([[D|CYCLE]|CYCLES],EDGES,BLOCK):- TAKE(EDGES,D,_),!,
    COMBINE([CYCLE|CYCLES],EDGES,BLOCK).
COMBINE([[D|CYCLE]|CYCLES],EDGES,BLOCK):- COMBINE([CYCLE|CYCLES],[D|EDGES],BLOCK).
COMBINE([[]|CYCLES],EDGES,BLOCK):- COMBINE(CYCLES,EDGES,BLOCK).
COMBINE([],BLOCK,BLOCK).
 
DIFFERENCE([D|GRAPH],BLOCK,GRAPH1):- TAKE(BLOCK,D,BLOCK1),!,
  DIFFERENCE(GRAPH,BLOCK1,GRAPH1).
DIFFERENCE([D|GRAPH],BLOCK,[D|GRAPH1]):- DIFFERENCE(GRAPH,BLOCK,GRAPH1).
DIFFERENCE([],_,[]).
 
MEMBER(TOP,[TOP|_]):- !.
MEMBER(TOP,[_|TOPS]):- MEMBER(TOP,TOPS).