program aa;
var
a,b,c,d,e,f,i,j,m,n,max:longint;
sum:int64;
l:array[1..1000]of longint;
f1,f2:text;
begin
 assign(f1,'best.in');
 assign(f2,'best.out');
 reset(f1);
 rewrite(f2);
 readln(f1,n);
 m:=n;
 sum:=1;
 if n=1 then writeln(f2,'1')
 else
 if n=2 then writeln(f2,'2')
 else
 if n=3 then writeln(f2,'3')
 else
 if n=4 then writeln(f2,'4')
 else
 if n=5 then writeln(f2,'6')
 else
 begin
 for i:=2 to n do
  if m-i>=0 then
   m:=m-i
  else
  begin
   a:=i-1;
   break;
  end;
 l[1]:=1;
 for i:=2 to a do
  l[i]:=i;
  if a-m<=0 then l[2]:=l[2]+m else
 l[a-m+1]:=l[a-m+1]+m;
 for i:=2 to a do
  sum:=sum*l[i];
 writeln(f2,sum);
 end;
 close(f1);close(f2);
end.