l = int(input())
n = int(input())
dp = [[-1 for i in range(l+1)] for j in range(n+1)]

a = list(map(int,input().split()))
dp[0][0] = 0
for i in range(n):
    for j in range(l+1):
        dp[i+1][j] = dp[i][j]
    for j in range(l+1):
        if j+a[i] <= l:
            if dp[i][j] >= 0:
                dp[i+1][j+a[i]] = max(dp[i+1][j+a[i]],dp[i][j]+1)
ma = 0
for i in dp[-1]:
    ma = max(ma,i)
print(ma)