type mtype=array [0..256] of integer;

var s:string;

a:mtype;

k,n,h:integer;

procedure zhuan(s:string);

var i:longint;

begin

for i:=1 to h do

case s[i] of

'0','1','2','3','4','5','6','7','8','9':a[i]:=ord(s[h-i+1])-48;

'a','b','c','d','f':a[i]:=ord(s[h-i+1])-86;

end;

end;

function check(a:mtype):boolean;

var i:integer;

begin

check:=true;

for i:=1 to h do

if a[i]<>a[h-i+1] then check:=false;

end;

procedure hui(var a:mtype);

var b:mtype; i:integer;

begin

for i:=1 to h do b[i]:=a[i];

for i:=1 to h do a[i]:=a[i]+b[h-i+1];

for i:=1 to h do

if a[i]>=k then

begin

a[i+1]:=a[i+1]+a[i] div k;

a[i]:=a[i] mod k;

end;

if a[h+1]<>0 then inc(h);

end;

begin

readln(k);

readln(s);

h:=length(s);

n:=0;

fillchar(a,sizeof(a),0);

zhuan(s);

while (n<=30)and(check(a)=false) do begin hui(a);inc(n); end;

if n>=30 then writeln('Impossible') else writeln(n);

end.

帮忙看看吧！！有一个数据总是过不去啊！！