var s,n,i,j,k:integer;
begin
assign(input,'p1029.in');
assign(output,'p1029.out');
reset(input);
rewrite(output);
read(n);
i:=1;
s:=1;
k:=1;
j:=1;
while i<n do
begin
i:=i+1;
if j+1>k then
begin
j:=1;
s:=1;
k:=k+1;
end
else
begin
j:=j+1;
s:=s+2;
end;
end;
write(s);
close(input);
close(output);
end.
菊花上长肿瘤
