How do I find duplicates in an array and display how many times they occurred?

Question

I'm working on a code that prints out duplicated integers from an array with the number of their occurrence. I'm not allowed to use LINQ, just a simple code. I think I'm so close but confused about how to get a correct output:

class Program {     static void Main(string[] args)     {                       int[] array = { 10, 5, 10, 2, 2, 3, 4, 5, 5, 6, 7, 8, 9, 11, 12, 12 };         int count = 1;         for (int i = 0; i < array.Length; i++)         {             for (int j = i; j < array.Length - 1 ; j++)             {                 if(array[j] == array[j+1])                   count = count + 1;             }             Console.WriteLine("\t\n " + array[i] + "occurse" + count);             Console.ReadKey();         }     } } 

Answer 1

Since you can't use LINQ, you can do this with collections and loops instead:

static void Main(string[] args) {                   int[] array = { 10, 5, 10, 2, 2, 3, 4, 5, 5, 6, 7, 8, 9, 11, 12, 12 };     var dict = new Dictionary<int, int>();          foreach(var value in array)     {         // When the key is not found, "count" will be initialized to 0         dict.TryGetValue(value, out int count);         dict[value] = count + 1;     }          foreach(var pair in dict)         Console.WriteLine("Value {0} occurred {1} times.", pair.Key, pair.Value);     Console.ReadKey(); }