Re: English versus German

LEE Sau Dan wrote:
"Helmut" == Helmut Wollmersdorfer <helmut@xxxxxxxxxxxxxxxxx> writes:

>> Did you learn the following in that course?

>> 1) Quick sort, and its worst case behaviour; 2) Hash tables, and
>> how to design good hash functions; 3) Self-balancing binary
>> search trees, e.g. AVL, red-black trees; 4) Recursion, and
>> tail-recursion; 5) Pointers (or references); 6) Dynamic
>> programming; 7) Why comparison-based sorting algorithms cannot do
>> better than o(n log n)?

Helmut> An application programmer does not need to know this topics,
Helmut> except 4) and 5).

Helmut> Most of your list are algorithms still implemented in an
Helmut> installable library. There is no need to reinvent the wheel.

You don't need to reinvent the wheel. There are many wheels ready to
use. But it helps a lot if you know how a wheel works! You do need to
pick the appropriate wheel for your specific application. Choosing the
wrong wheel (e.g. a steel wheel on muddy ground) makes it crawl!

e.g. I have seen CS graduates using an (unsorted) array to implement a
mathematical set (as in set theory), and wondering why his program runs
so slowing when managing sets of millions of integer ids. When I told
him to use a hash table instead, the program ran at least 1000 times
faster.

This indicates that his ignorance lies in what technology is
available, not in how the technology work. Not that I agree
completely with Helmut, but this does not support your argument.

Tak
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