Simple producer-consumer example C# Dictionary -

i make first steps in parallel programming. wrote simplest code, result confused. code takes top 10 recent items producer-consumer pattern. 1 consumer , 1 producer. 2 consumers in works better, incorrect too.

  public static void producerconsumer(string path)     {         var capacity = 50000;         var collection = new blockingcollection<string>(capacity);         var dict = new dictionary<string, int>();         var tasks = new list<task<dictionary<string, int>>>();         var producer = task.factory.startnew(() =>         {              parallel.foreach(file.readlines(path), (line) =>             {                 collection.add(line);             });             collection.completeadding();         });          (int = 0; < 1; i++)         {             var consumer = task.factory.startnew<dictionary<string, int>>(() =>             {                 var localdict = new dictionary<string, int>();                 while (!collection.iscompleted)                 {                     string line;                     if (collection.trytake(out line))                     {                         map(line, localdict);                     }                 }                 return localdict;             });             tasks.add(consumer);         }         int count = 0;         while (tasks.count > 0)         {             var id = task.waitany(tasks.toarray());              var res = tasks[id].result;             count += res.sum(k => k.value);             aggregate(res, dict);             tasks.removeat(id);         }         console.writeline($"values sum : {count}");         showresult(dict);         showtotal(dict, "end");       }     public static void map(string line, dictionary<string, int> dict)     {         var parts = line.split(new string[] { ";" }, stringsplitoptions.removeemptyentries);         var streetname = parts[3];         if (dict.keys.contains(streetname))         {             dict[streetname]++;         }         else         {             dict.add(streetname, 1);         }     }     public static void showresult(dictionary<string, int> dict)     {          var res = dict.orderbydescending(r => r.value).take(10).tolist();          foreach (var key in res)         {             console.writeline($"{key.key} - {key.value}");         }     }     public static void aggregate(dictionary<string, int> part, dictionary<string, int> main)     {          foreach (var key in part.keys)         {             if (main.keys.contains(key))             {                 main[key] += part[key];             }             else             {                 main.add(key, 1);             }         }     }      public static void showtotal(dictionary<string, int> dict, string mark = null)     {         console.writeline($"{mark ?? ""} keys: {dict.keys.count} - values:{dict.sum(s => s.value)}");     } 

while debugging shows correct steps, result shows 1 hit per item , incorrect total.

if understand algorithm, should be:

main.add(key, part[key])