C# program to find all duplicate elements in an integer array

Firstly, set the array with duplicate elements.

int[] arr = {    24,    10,    56,    32,    10,    43,    88,    32 };

Now declare a Dictionary and loop through the array to get the repeated elements.

var d = new Dictionary < int, int > (); foreach(var res in arr) {    if (d.ContainsKey(res))          d[res]++;    else    d[res] = 1; }

Example

 Live Demo

using System; using System.Collections.Generic; namespace Demo {    public class Program {       public static void Main(string[] args) {          int[] arr = {             24,             10,             56,             32,             10,             43,             88,             32          };          var d = new Dictionary < int, int > ();          foreach(var res in arr) {             if (d.ContainsKey(res))             d[res]++;             else             d[res] = 1;          }          foreach(var val in d)          Console.WriteLine("{0} occurred {1} times", val.Key, val.Value);       }    } }

Output

24 occurred 1 times 10 occurred 2 times 56 occurred 1 times 32 occurred 2 times 43 occurred 1 times 88 occurred 1 times