🔒 Locked

unique texfile strings

Started by cozzie Nov 16, 2012 at 9:04 PM 0 replies 1.3k views

Original Post

Nov 16, 2012 at 9:04 PM

Hi,

I'm strugging/ staring blind at a fairly simple 'issue'.

I have an array of strings and want to find out the number of unique strings, the strings are stored in tempTexFiles[]:

[source lang="cpp"] int pNrUniqueMaterials = 1;
bool NEW = false;
for(int texcount=1;texcount {
for(int tlist=0;tlist {
if(tempTexFiles[texcount] == tempTexFiles[tlist]) break;
else NEW = true;
}
if(NEW)
{
pNrUniqueMaterials++;
NEW = false;
}
}

mNrMaterials = pNrUniqueMaterials;
[/source]

Probably something to simple for words, been staring at it for an hour.

The results now is 5 and should be 3....

Any help is really appriciated.

greets,
Cris

alvaro

Nov 16, 2012 at 9:31 PM

Can this be moved to General Programming or For Beginners? It has nothing to do with graphics...

Your algorithm is broken. As long as not all strings are identical, NEW will always be true and you will end up with pNrUniqueMaterials == pNrMaterials. A correct algorithm in the style of yours would go something like this:

 int pNrUniqueMaterials = 0;
 for (int i = 0; i < pNrMaterials; ++i) {
 if (std::find(tempTexFiles, tempTexFiles+i, tempTexFiles) == tempTexFiles+i)
 ++pNrUniqueMaterials;
 }

If you have a large number of strings and this takes too long, you can do better, for instance by using an unordered_set.

Topic Locked

This topic has been locked by a moderator. New replies are not allowed.