#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,k,year=1,zao=0;
	cin>>n>>k;
	double fang=200;
	zao=n;
	while(year<=20){
		if(zao>=fang){
			cout<<year;
			break;
		} 
		year++;
		zao=n*year;
		fang=fang+fang*(k*1.0/100);
	}
	if(year<=20)
	    cout<<year;
	else
	    cout<<"impossible";
	return 0;
}