using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Console.Write("Insert length of array - ");

        int n = int.Parse(Console.ReadLine());

        List<int> arr = new List<int> ();

        for (int i = 0; i < n; i++){

        arr.Add(int.Parse(Console.ReadLine()));

         }

        foreach (int j in arr) {

        Console.Write(j + " ");

        }

         Console.Write("\n");

        for (int k = 0; k < n; k++){

          for (int m = k+1; m < n; m++){

            if(arr[k] == arr[m]){

             Console.Write(k + " , " + m + " ");

            }

          }

        }

    }

}