L = int(input())
N = int(input())
W = list(map(int, input().split()))
V = [1] * N
dp = []
for i in range(N+1):
    l = []
    for i in range(L):
        l.append(0)
    dp.append(l)

for i in range(N):
    for j in range(L):
        if j - W[i] < 0:
            dp[i+1][j] = max(dp[i][j], dp[i+1][j-1])
        else:
            dp[i+1][j] = max(dp[i][j], dp[i][j-W[i]]+V[i], dp[i+1][j-1])

print(dp[N][L-1])