var a:array[1..100] of integer;
    i,k,n,d:integer;
    f,g:text;
begin
assign(f,'ciur.in');
reset(f);
readln(f,n);
close(f);
assign(g,'ciur.out');
rewrite(g);
k:=0;
for i:=1 to n do
    begin
    inc(k);
    a[i]:=k;
    end;


    k:=0;

    repeat
    inc(k,2);
    a[k]:=0;
    until k>n;

    k:=0;
    repeat
    inc(k,3);
    a[k]:=0;
    until k>n;

    k:=0;
    repeat
    inc(k,5);
    a[k]:=0;
    until k>n;

    k:=0;
    repeat
    inc(k,7);
    a[k]:=0;
    until k>=n;

for i:=2 to n do
    if a[i]<>0 and a[i]<>1 then inc(d);
writeln(g,d);
close(g);
end.