using System;

using System.Linq;

using System.Collections.Generic;                   

​

public class Program

{

    public static void Main()

    {

        var esperados = new int[] {1, 2, 3};

        var obtidos = new int[] {3, 1, 2};

        Console.WriteLine(ContainsAll(esperados, obtidos));

    }

    public static bool ContainsAll<T>(IEnumerable<T> expected, ICollection<T> found) {

        return expected.Intersect(found).Distinct().Count() == found.Count;

    }

}