using System;

​

public class Program

{

    static bool AllIncluded(int[] a, int[] b)

    {

        foreach (int num in b)

            if (Array.IndexOf(a, num) == -1)

                return false;

        return true;

    }

​

    public static void Main()

    {

        int[] a = { 1, 2, 3, 4, 5 };

        int[] b = { 2, 3, 5 };

​

        Console.WriteLine(AllIncluded(a, b));

    }

}

​