st=list()
ans=0
n=int(input())
m=int(input())
s=input()
lis=s.split()
lis=[int(i) for i in lis]
for i in range(n):
    st.append(True)
for i in lis:
    for j in range(len(st)):
        if (j+1)%i==0:
            if(st[j])==True:
                st[j]=False
            else:
                st[j]=True
#print(st)
for i in st:
    if i==True:
        ans+=1
print(ans)