var n,i,j,k,p,u:int64;
    f:text;
begin
{   assign(f,'fact.in');
   reset(f);}
   read(n);
 {  close(f);
   assign(f,'fact.out');
   rewrite(f);}
   if n=0 then writeln(1)
   else
   begin
   while p+163<=n do
   begin
   i:=i+625;
   p:=p+156;
   end;
   while p+32<=n do
   begin
   i:=i+125;
   p:=p+31;
   end;
   while p+6<=n do
   begin
   i:=i+25;
   p:=p+6;
   end;
   while p+1<=n do
   begin
   i:=i+5;
   p:=p+1;
   end;
   end;
   writeln(i);


  { close(f);}
end.