program factorial;
var f,g:text;
    i,p,gasit,nr,i1:longint;
begin
     assign(f,'fact.in');
     assign(g,'fact.out');
     reset(f);
     rewrite(g);
     read(f,p);
     gasit:=0;
     i:=0;
          if p>99999999 then
          begin
               i:=400000010;
               gasit:=99999999;
          end else
          if p>49999999 then
          begin
               i:=200000005;
               gasit:=49999999;
          end else
          if p>9999999 then
          begin
               i:=40000005;
               gasit:=9999999;
          end else
          if p>4999999 then
          begin
               i:=20000000;
               gasit:=4999999;
          end else
          if p>999999 then
          begin
               i:=4000000;
               gasit:=999999;
          end else
          if p>499999 then
          begin
               i:=2000000;
               gasit:=499999;
          end else
          if p>99999 then
          begin
               i:=400000;
               gasit:=99999;
          end else
          if p>49999 then
          begin
               i:=200005;
               gasit:=49999;
          end else
          if p>9999 then
          begin
               i:=40005;
               gasit:=9999;
          end else
          if p>999 then
          begin
               i:=4000;
               gasit:=999;
          end else
          if p>99 then
          begin
               i:=400;
               gasit:=99;
          end;
     while(gasit<p) do
     begin
          i:=i+5;
          i1:=i;
          while (i1 mod 3125=0) do
          begin
               i1:=i1 div 3125;
               gasit:=gasit+5;
          end;
          while(i1 mod 125=0) do
          begin
               i1:=i1 div 125;
               gasit:=gasit+3;
          end;
          while( i1 mod 5 =0) do
          begin
               i1:=i1 div 5;
               gasit:=gasit+1;
          end;
     end;
     if p=0 then nr:=1
     else nr:=1;
     write(g,nr);
     close(f);
     close(g);
end.