How to Find Duplicate Values in Arrays?

Question

I am working on SQLite and I have written a query which returns me two arrays ItemsArray and CustomersIDArray as:

ItemsArray
Element at Index 0 = Off White,
         


        

Answer 1

Use NSCountedSet like below

NSMutableArray *ary_res = [[NSMutableArray alloc] init];
    NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:@"11",@"13",@"34",@"9",@"13",@"34",@"9",@"2",nil];
    NSCountedSet *set = [[NSCountedSet alloc] initWithArray:array];
    for(id name in set)
    {
        if([set countForObject:name]==2)
            [ary_res addObject:name];
    }
    //
    NSLog(@"%@",ary_res);