How to sort 100 million numbers in a file?

Answer 1

There are many sorting algorithms, some of which take N^2 sorts (10^16 in this case) and some which take only 10 * ln(N) (or about 2*10^9) sorts. (The idea being that there are smarter ways to put a new number into an already-sorted list than comparing it with every item in the list. Such as a binary method, looking at the midpoint of the list, then the midpoint of the half that that the first comparison determined, etc.) See the ref.

Answer 2

It can be done through a C or Fortran program but there may be memory problems. I don't know. If you use Javascript, you may still get an error message,"File too large."
I don't know if Excel or some other program can handle it.
Here is a javascript example, but only has 10 values and they are not in a file. They're within the program.





Databases contain several millions of info and they sort immediately. So, there must be a better way.

Answer 3

cidyah:

to sort 10^8 numbers your program will have to perform about 10^16 comparisons. Assuming 10^9 op/s it will take at least one year to finish.

There *is* a better way indeed.

Answer 4

I think the point of the question is that 100 million is quite a lot.

Excel would cr@p itself before it even started.

This seems like a non-trivial problem.

Answer 5

1 2 3 so forth and so on

Good Luck

Answer 6

MS Access would be good for this.

If you know how to write scripts then any C++ program can help.

Can you be more specific?

Answer 7

If you mean in order, you can use excel. It has a nifty button that will do this for you.

Answer 8

try numerical order

Answer 9

use excel.