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CSharp · Console

/Program.cs

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

using System.Threading.Tasks;
					
public class Program
{
	public static void Main(string[] args)
        {
		foreach(var entry in Format("Id n o 2") )
            Console.WriteLine(entry);
        }

	
	public static IEnumerable<string> Format(string s)
    {
        var chunkSize = 2;
        return s.Where((x,i) => i % chunkSize == 0).Select((x,i) => s.Skip(i * chunkSize).Take(chunkSize)).Select(x=> string.Join("", x));

    }

    
}