[X,Y]

le(0,Y) -> true.
le(s(X),0) -> false.
le(s(X),s(Y)) -> le(X,Y).
minus(0,Y) -> 0.
minus(s(X),Y) -> ifMinus(le(s(X),Y),s(X),Y).
ifMinus(true,s(X),Y) -> 0.
ifMinus(false,s(X),Y) -> s(minus(X,Y)).
quot(0,s(Y)) -> 0.
quot(s(X),s(Y)) -> s(quot(minus(X,Y),s(Y))).

