#include <bits/stdc++.h>
using namespace std;
int N;
char shu[10086];
bool pan()
{
	int len=strlen(shu);
	for(int i=0;i<=len/2;i++)
	{
		if(!shu[i]-'0'==shu[len-i]-'0')
		    return false;
	}
	return true;
}
void jia()
{
	char cun[10086];
	int len=strlen(shu);
	for(int i=len-1;i>=0;i--)
	    cun[len-i]=shu[i];
	for(int i=1;i<len;i++)
	{
		cun[i]=(cun[i]+shu[i]-'0')+'0';
		cun[i+1]=(cun[i+1]+cun[i]-'0')/N;
	    cun[i]=(cun[i]-'0')%N;
	}
	len++;
	while(!cun[len])
	    len--;
	swap(cun,shu);
}
int main()
{
	cin>>N;
	cin>>shu;
	for(int i=1;i<=30;i++)
	{
		if(!pan())
		{
			cout<<i<<endl;
			return 0;
		}
		jia();
	}
	cout<<"Impossible";
	return 0;
}