LINQ Query to display the array elements and the number of times they occur

This is the code to display the elements of an array and the number of times they occur using System;

Take a Console Application and write the code in Main method

using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplicationlinq
{
class Program
{
static void Main(string[] args)
{
int[] arr = { 10, 20, 30, 30, 10 };
//use the Group By function with a lambda
//expression
var q = arr.GroupBy(a => a);

//use the Generic interface IGrouping
foreach (IGrouping<int, int> z in q)
{
Console.WriteLine(z.Key + "---" + z.Count());
}
}
}
}

output:
10--2
20--1
30--2