[SOLVED] What is the efficient way to search trough NSArray

What is the efficient way to search trough NSArray

I have NSStrings in my array:

i[0] = axxx
i[1] = axyz
i[2] = axxy
i[3] = abcd

I want to pass a search string to find all needed strings. For example if I pass "ax" then it will return 3 strings, if I pass "axx" then it will return 2 string.

Performance is critical here as well. The method should look like this:

- (NSArray *)searchString:(NSString *)search;

Noramlly I use NSPredicate, but this time I need to use maybe Prefix Tree or Binary Tree, I am not sure but it should be faster. Any suggestion or links to implementation.

Solution

Hope this solution will satisfy you.

- (NSArray *)searchString:(NSString *)search{

    NSIndexSet *indexes = [dataArray indexesOfObjectsPassingTest:
                           ^BOOL (id obj, NSUInteger i, BOOL *stop) {
                               NSString *myObj = obj;
                               return [myObj containsString:search];
                           }];
    NSArray *results = [dataArray objectsAtIndexes:indexes];

    return results;

}