program veverix;
var a, a2 : array[1..20] of int64;
    i : integer;
    n,z : int64;
    t,t2 : text;
begin
assign(t,'fact.in');
assign(t2,'fact.out');
reset(t);
rewrite(t2);
readln(t,n);
a[1]:=5;
for i:=2 to 25 do
a[i]:=a[i-1]*5;

a2[1]:=1;
for i:=2 to 25 do
a2[i]:=(a2[i-1]*5)+1;



while (n>0) do
begin


for i:=20 downto 1 do
if n>=a2[i] then
        begin
        n:=n-a2[i];
        z:=z+a[i];
        end;
end;
writeln(t2,z);
close(t);
close(t2);
end.