a
var
n,p:longint;
begin
readln(n);
p:=1;
repeat
p:=p*(n mod 10);
n:=n div 10;
until n=0;
writeln(p);
readln;
end.
b
var
n:longint;
k:integer;
begin
readln(n);
while n>3 do
begin
if n mod 3=0 then inc(k);
n:=n div 3;
end;
writeln(k);
readln;
end.