var
k,x,d,n:int64;
i,p:longint;
v:array[1..1000000] of boolean;
f,g:text;
begin
assign(f,'light2.in');reset(f);
assign(g,'light2.out');rewrite(g);
readln(f,n);
readln(f,p);
for i:=1 to n do
v[i]:=false;
for i:=1 to p do
begin
read(f,d);
x:=d;
while x<=n do
begin
v[x]:=not(v[x]);
x:=x+d;
end;
end;
for i:=1 to n do
if v[i]=true then inc(k);
writeln(g,k);
close(g);
end.