program rle;
    test := "WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW";

    print("Input:");
    print(test);
    print("Encoded:");
    print(enc := rlencode(test));
    print("Decoded:");
    print(rldecode(enc));

    proc rlencode(s);
        loop while s /= "" do
            part := span(s, s(1));
            r +:= str #part + part(1);
        end loop;
        return r;
    end proc;

    proc rldecode(s);
        loop while s /= "" do
            num := span(s, "0123456789");
            item := notany(s, "");
            r +:= val num * item;
        end loop;
        return r;
    end proc;
end program;