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CSharp · Console

/Program.cs

using System;
using System.Linq;

public class Program
{
    public static void Main(string[] args)  
    {  
		const string input = "abcfed";
		
		var random = new Random();

		for	(int i = 0; i < 10; i++)
		{
    		var randomized = new string(input.OrderBy(letter => random.Next()).ToArray());
			Console.WriteLine(randomized);
		}
	}
 }