(VAR u x y z )
(RULES 
        f(j(x, y), y) -> g(f(x, k(y)))
        f(x, h1(y, z)) -> h2(0, x, h1(y, z))
        g(h2(x, y, h1(z, u))) -> h2(s(x), y, h1(z, u))
        h2(x, j(y, h1(z, u)), h1(z, u)) -> h2(s(x), y, h1(s(z), u))
        i(f(x, h(y))) -> y
        i(h2(s(x), y, h1(x, z))) -> z
        k(h(x)) -> h1(0, x)
        k(h1(x, y)) -> h1(s(x), y)
        
)