# coding: utf-8

import numpy as np

L = int(input())
N = int(input())
length = [int(i) for i in input().split()]

memo = -1*np.ones((N+1,L+1))

def search(i,j):
    if memo[i,j] != -1:
        return memo[i,j]
    else:
        if i == N:
            res = 0
        elif j < length[i]:
            res = search(i+1,j)
        else:
            res = max(search(i+1, j), search(i+1, j - length[i]) + 1)
        memo[i,j] = res

        return res

print(search(0,L))