Problem05SubsetSums

using System;

class Problem05SubsetSums
{
    static void Main()
    {
        short result = 0;
        long temp = 0;
        string combination = "";
        long s = long.Parse(Console.ReadLine());
        byte n = byte.Parse(Console.ReadLine());
        long[] numberN = new long[n];
        for (int i = 0; i < n; i++)
        {
            numberN[i] = long.Parse(Console.ReadLine());
        }

        for (int i = 1; i < Math.Pow(2, n); i++)
        {
            combination = Convert.ToString(i, 2).PadLeft(n, '0');
            temp = 0;
            for (int a = 0; a < combination.Length; a++)
            {
                if (combination[a] == '1')
                {
                    temp = temp + numberN[a];
                }
            }
            if (temp == s)
            {
                result++;
            }
        }
        Console.WriteLine(result);
    }
}