Lampochki

uses math;
var
 q:array[0..100001,0..3] of longint;
 a,b:array[0..500010] of longint;
 x,y,yy,i,j,z,t,q1,q2:longint;
 st,stt:array[0..50100] of string;
 p:array[1..50000] of boolean;
 s,ss,sw:string;
// x,y,xx,yy:extended;
 c:char;
 w:array['a'..'z'] of longint;
 xx,n,m,k,ans,tp:int64;


function nok(a,b:int64):int64;
var
 i,j:int64;
begin
 i:=a;j:=b;
 while i*j<>0 do
  if i>j then i:=i mod j else j:=j mod i;
 nok:=(a*b) div (i+j);

end;

begin
assign(input,'input.txt');reset(input);
assign(output,'output.txt');rewrite(output);
 read(n,m);
 for i:=1 to m do read(a[i]);
 z:=0;
 for i:=1 to m do
  begin
   for j:=1 to z do
    begin
     tp:=nok(q[j,1],a[i]);
     if tp<=n then begin
                    inc(z);
                    q[z,1]:=tp;q[z,2]:=q[j,2]*(-2);
                   end;

    end;
    inc(z);
    q[z,1]:=a[i];q[z,2]:=1;
  end;
 ans:=0;
 for i:=1 to z do
  begin
   ans:=ans+(n div q[i,1])*q[i,2];
  end;
 write(ans);
end.