l=int(input())
n=int(input())
W=list(map(int,input().split()))

DP=[-1]*(l+1)
DP[0]=0
DP[W[0]]=1

for i in range(1,n):
    for j in range(l-W[i],-1,-1):
        if DP[j]==-1:
            continue
        DP[j+W[i]]=max(DP[j+W[i]],DP[j]+1)

print(max(DP))