program fact;
var f,g:text;
    n,k,p,k1,cinci:longint;
begin
assign(f,'fact.in'); reset(f);
read(f,p); close(f);
n:=p*5; k:=25; cinci:=0;
while k<=n do
  begin
  if k mod 50=0 then
    cinci:=cinci+2
  else
    cinci:=cinci+1;
  k:=k+25;
  end;
assign(g,'fact.out'); rewrite(g);
if p=0 then
  write(g,1)
else
  writeln(g,n-(cinci*5)-5); close(g);
end.