USES CRT;VAR N,I,SO,CODE,X

Bài 1:

uses crt;

var n,i,so,code,x:integer;

f,g:text;

c,s:string;

h:int64;

begin

clrscr;

assign(f,'persist.inp');

reset(f);

assign(g,'persist.out');

rewrite(g);

readln(f,n);

str(n,s);

while length(s)<>1 do

begin

x:=x+1; h:=1;

for i:=1 to length(s) do

begin

val(s[i],so,code);

h:=h*so;

end;

str(h,s);

end;

writeln(x);

close(f);

close(g);

readln;

end.