(STRATEGY
    INNERMOST)

(VAR
    x2 x1)
(RULES
    rec[even_0][1](0()) -> True()
    rec[even_0][1](S(0())) -> False()
    rec[even_0][1](S(S(x2))) -> rec[even_0][1](x2)
    main(x1) -> rec[even_0][1](x1))