static void Main(string[] args) { List <KeyValuePair <string, int> > source = new List <KeyValuePair <string, int> >(); Random random = new Random(); for (int i = 0; i < 10000000; i++) { source.Add( new KeyValuePair <string, int>((i % 1000).ToString(), random.Next())); } { var c = new Concordance <string, int>( new SortedDictionary <string, ConcordanceItem <string, int> >() ); c.Build(source.AsParallel()); } }