void
m3(integer i)
{
    text s;

    s = itoa(i);
    if (s[0] == '-') {
        s = delete(s, 0);
    }

    if (~s < 3) {
        v_integer(i);
        v_text(" has not enough digits\n");
    } elif (~s & 1) {
        o_form("/w9/: ~\n", i, cut(s, ~s - 3 >> 1, 3));
    } else {
        v_integer(i);
        v_text(" has an even number of digits\n");
    }
}

void
middle_3(...)
{
    integer i;

    i = 0;
    while (i < count()) {
        m3($i);
        i += 1;
    }
}

integer
main(void)
{
    middle_3(123, 12345, 1234567, 987654321, 10001, -10001, -123, -100, 100,
             -12345, 1, 2, -1, -10, 2002, -2002, 0);

    return 0;
}