(VAR f x xs y z )
(RULES 
        app(app(le,0),y) -> true
        app(app(le,app(s,x)),0) -> false
        app(app(le,app(s,x)),app(s,y)) -> app(app(le,x),y)
        app(app(eq,0),0) -> true
        app(app(eq,0),app(s,y)) -> false
        app(app(eq,app(s,x)),0) -> false
        app(app(eq,app(s,x)),app(s,y)) -> app(app(eq,x),y)
        app(app(app(if,true),x),y) -> x
        app(app(app(if,false),x),y) -> y
        app(minsort,nil) -> nil
        app(minsort,app(app(cons,x),y)) -> app(app(cons,app(app(min,x),y)),app(minsort,app(app(del,app(app(min,x),y)),app(app(cons,x),y))))
        app(app(min,x),nil) -> x
        app(app(min,x),app(app(cons,y),z)) -> app(app(app(if,app(app(le,x),y)),app(app(min,x),z)),app(app(min,y),z))
        app(app(del,x),nil) -> nil
        app(app(del,x),app(app(cons,y),z)) -> app(app(app(if,app(app(eq,x),y)),z),app(app(cons,y),app(app(del,x),z)))
        app(app(map,f),nil) -> nil
        app(app(map,f),app(app(cons,x),xs)) -> app(app(cons,app(f,x)),app(app(map,f),xs))
        app(app(filter,f),nil) -> nil
        app(app(filter,f),app(app(cons,x),xs)) -> app(app(app(app(filter2,app(f,x)),f),x),xs)
        app(app(app(app(filter2,true),f),x),xs) -> app(app(cons,x),app(app(filter,f),xs))
        app(app(app(app(filter2,false),f),x),xs) -> app(app(filter,f),xs)
        
)