var N,i:integer;
begin
readln(N);
writeln((N+1)/2);
end.
var N,sum,i:integer;
for i:=1 to N do if i mod 2<>0 then begin writeln(i); sum:=sum+i; end;
writeln(sum);
var N,i:integer;
begin
readln(N);
writeln((N+1)/2);
end.
var N,sum,i:integer;
begin
readln(N);
for i:=1 to N do if i mod 2<>0 then begin writeln(i); sum:=sum+i; end;
writeln(sum);
end.