import sys
input = sys.stdin.readline

L = int(input())
N = int(input())
W = list(map(int, input().split()))
dp = [0] * (L + 1)
for w in W:
    for j in range(L, w - 1, -1):
        dp[j] = max(dp[j], dp[j - w] + 1)
print(dp[L])