pub unsafe fn lookup_ord_(&mut self, k0: u64) -> u16 {
        let mut a = 16;
        let mut b = self.size();
        assert!(b <= 4096);

    pub unsafe fn lookup_ord_(&mut self, k0: u64) -> (u16, u16) {
        let mut a = 0;
        let mut b = (self.size() - 16) / 24;

            let mid = (a + b) / 2 - 16;
            let mid = 16 + mid - (mid % 24);
            let k = *(self.p.offset(mid as isize) as *mut u64);

            let mid = (a + b) / 2;
            let k = *(self.p.offset((16 + mid * 24 + 8) as isize) as *mut u64);

            } else if k == k0 {
                a = mid;
                b = mid;
                break

        a

        (16 + a * 24, 16 + b * 24)

        let off = self.lookup_ord_(k0) as isize;
        let k = *(self.p.offset(off) as *mut u64);

        let (off, _) = self.lookup_ord_(k0);
        let off = off as isize;
        let k = *(self.p.offset(off + 8) as *mut u64);

            Some(*(self.p.offset(off + 8) as *mut u64))

            Some(*(self.p.offset(off + 16) as *mut u64))

        let off = self.lookup_ord_(k0);

        let (_, off) = self.lookup_ord_(k0);