Input TRS: 1: active(zz(zz(X,Y),Z)) -> mark(zz(X,zz(Y,Z))) 2: active(zz(X,nil())) -> mark(X) 3: active(zz(nil(),X)) -> mark(X) 4: active(and(tt(),X)) -> mark(X) 5: active(isList(V)) -> mark(isNeList(V)) 6: active(isList(nil())) -> mark(tt()) 7: active(isList(zz(V1,V2))) -> mark(and(isList(V1),isList(V2))) 8: active(isNeList(V)) -> mark(isQid(V)) 9: active(isNeList(zz(V1,V2))) -> mark(and(isList(V1),isNeList(V2))) 10: active(isNeList(zz(V1,V2))) -> mark(and(isNeList(V1),isList(V2))) 11: active(isNePal(V)) -> mark(isQid(V)) 12: active(isNePal(zz(I,zz(P,I)))) -> mark(and(isQid(I),isPal(P))) 13: active(isPal(V)) -> mark(isNePal(V)) 14: active(isPal(nil())) -> mark(tt()) 15: active(isQid(a())) -> mark(tt()) 16: active(isQid(e())) -> mark(tt()) 17: active(isQid(i())) -> mark(tt()) 18: active(isQid(o())) -> mark(tt()) 19: active(isQid(u())) -> mark(tt()) 20: active(zz(X1,X2)) -> zz(active(X1),X2) 21: active(zz(X1,X2)) -> zz(X1,active(X2)) 22: active(and(X1,X2)) -> and(active(X1),X2) 23: zz(mark(X1),X2) -> mark(zz(X1,X2)) 24: zz(X1,mark(X2)) -> mark(zz(X1,X2)) 25: and(mark(X1),X2) -> mark(and(X1,X2)) 26: proper(zz(X1,X2)) -> zz(proper(X1),proper(X2)) 27: proper(nil()) -> ok(nil()) 28: proper(and(X1,X2)) -> and(proper(X1),proper(X2)) 29: proper(tt()) -> ok(tt()) 30: proper(isList(X)) -> isList(proper(X)) 31: proper(isNeList(X)) -> isNeList(proper(X)) 32: proper(isQid(X)) -> isQid(proper(X)) 33: proper(isNePal(X)) -> isNePal(proper(X)) 34: proper(isPal(X)) -> isPal(proper(X)) 35: proper(a()) -> ok(a()) 36: proper(e()) -> ok(e()) 37: proper(i()) -> ok(i()) 38: proper(o()) -> ok(o()) 39: proper(u()) -> ok(u()) 40: zz(ok(X1),ok(X2)) -> ok(zz(X1,X2)) 41: and(ok(X1),ok(X2)) -> ok(and(X1,X2)) 42: isList(ok(X)) -> ok(isList(X)) 43: isNeList(ok(X)) -> ok(isNeList(X)) 44: isQid(ok(X)) -> ok(isQid(X)) 45: isNePal(ok(X)) -> ok(isNePal(X)) 46: isPal(ok(X)) -> ok(isPal(X)) 47: top(mark(X)) -> top(proper(X)) 48: top(ok(X)) -> top(active(X)) Number of Rules: 48 Direct POLO(mPol) ... failed.