L = int(input())
N = int(input())
W = list(map(int, input().split()))

INF = 1<<60
dp = [-INF]*(L+1)
dp[0] = 0
for w in W:
  for i in range(L+1)[::-1]:
    if i+w<=L and dp[i+w]<dp[i]+1:
      dp[i+w] = dp[i]+1
ans = max(dp)
print(ans)