#yuki385

m=int(raw_input())
n=int(raw_input())
c=map(int,raw_input().split())
c.sort()
dp=[-1 for i in xrange(m+1)]
p=[True for i in xrange(m+1)]
p[0],p[1]=False,False
for i in xrange(2,m+1):
 if p[i]:
  j=i*2
 while j<=m:
  if p[j]:
   p[j]=False
  j+=i
dp[m]=0
for i in range(n):
 for j in range(m,-1,-1):
  k=j-c[i]
  if dp[j]!=-1 and k>=0:
   dp[k]=max(dp[k],dp[j]+1)
res=0
for i in range(m+1):
 if p[i] and dp[i]>=0:
  res+=dp[i]
res+=m/c[0]
print res