def make_change(n, coins)
  dp = Array.new(n + 1, 0)
  dp[0] = 1
  coins.each do |coin|
    (coin..n).each do |i|
      dp[i] += dp[i - coin]
    end
  end
  dp[n]
end

n, _m = gets.split.map(&:to_i)
coins = gets.split.map(&:to_i)
puts make_change(n, coins)