(VAR x y )
(RULES 
        minus(x, 0) -> x
        minus(s(x), s(y)) -> minus(x, y)
        le(0, y) -> true
        le(s(x), 0) -> false
        le(s(x), s(y)) -> le(x, y)
        quot(0, s(y)) -> 0
        quot(s(x), s(y)) -> s(quot(minus(s(x), s(y)), s(y)))
        
)