List Out Of Memory Exception

Question

I want to fill a list like below :

    List<string> list_lines = new List<string>();
    for (double num = double.Parse(txtStart.Text); num < 99999999; num++)
    {
        list_lines.Add(num.ToString());
    }

but those codes cause error at 33,554,432 and that error :
Out Of Memory Exception
I want to work with that list, what is the replacement of that or how can i fix that error?

thanks in advance

On my system I run out of memory at `33,554,432`; tried it with double and int and with or without parsing, but it stops at the exact same iteration in all cases. — John Willemse, Apr 09 '13 at 06:39
Yes, me too, that's what I wrote. The only thing that gives you more room is to drop the .ToString() and put the values in a list of ints instead of strings. However, you will still run out of memory with these kind of numbers. — John Willemse, Apr 09 '13 at 06:42
What is it that you're actually trying to achieve? There are a lot of different answers, but they depend on what you're trying to actually do. — Corey, Apr 09 '13 at 06:47

score 3 · Accepted Answer · answered Apr 09 '13 at 06:46

If you can replace List with IEnumerable than you can use following approach

    static IEnumerable<string> Gen()
    {
        for (double num = 0; num < 99999999; num++)
        {
            yield return num.ToString();
        }
    }

So basically you do not allocate memory, with further processing you have to keep in mind that you cannot call something like Gen().ToArray() this will produce the same issue. If you need list there is no way this will work.

score 1 · Answer 2 · answered Apr 09 '13 at 06:36

1

You can do some memory optimizations, e.g. only doing the parsing once:

var parsed_number = double.Parse(txtStart.Text);

List<string> list_lines = new List<string>();
for (double num = parsed_number; num < 99999999; ++num)
{
    list_lines.Add(num.ToString());
}

That might help with the memory usage.

answered Apr 09 '13 at 06:36

Erik Schierboom

16,301
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i removed that parsed_number from loop, still have that error in num -> 33,554,432 – SilverLight Apr 09 '13 at 06:42

score 0 · Answer 3 · answered Apr 09 '13 at 06:34

0

You don't have enough memory!
Each step of loop reserve memory. Whole loop need [99999999 * 99999999/2 * sizeof(double)] B. This is really big number

answered Apr 09 '13 at 06:34

Jacek

11,661
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score 0 · Answer 4 · answered Apr 09 '13 at 06:46

If you need the numbers, try this code instead:

int startNumber = int.Parse(txtStart.Text);
List<int> list_lines = new List<int>();

for (int i = startNumber; i < 99999999; i++)
{
    list_lines.Add(i);
}

That will run without problems. If you need the numbers as a string later, just convert them at the moment you retrieve them.

score 0 · Answer 5 · edited May 23 '17 at 12:29

0

I suggest John Willemse's answer - ints are faster than strings anytime..

Just convert to string when required - check out this link for the best possible method (of conversion) for your scenario:

Better way to cast object to int

edited May 23 '17 at 12:29

Community

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answered Nov 07 '13 at 07:49

shree harsha s

1

List Out Of Memory Exception

5 Answers5