#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)n;i++)
#define rep1(i,n) for(int i=1;i<=(int)n;i++)
#define sp(n) cout << fixed << setprecision(n)
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
typedef long long ll;
using namespace std;
int main(void){
    ll a,b;cin>>a>>b;
    for(ll res=b;res>=1;res--){
        ll buf=(a+res-1)/res;
        ll buf1=buf*res,buf2=(buf+1)*res;
        if((a<=buf1&&buf1<=b)&&(a<=buf2&&buf2<=b)){
            cout<<res<<endl;
            return 0;
        }
    }
}
#include <bits/stdc++.h>
using namespace std;
#define MOD 1000000007
#define ll long long
typedef pair<ll, ll> ii;
typedef vector<ll> vi;
typedef vector<bool> vb;
typedef vector<vi> vvi;
typedef vector<ii> vii;
typedef vector<vii> vvii;
#define pq priority_queue
#define ff first
#define ss second
#define pb push_back
#define tc int t; cin>>t; while(t--)
#define file_read(x,y) freopen(x, "r", stdin); \
                  freopen(y, "w", stdout);
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
   	double a,b;
   	cin >> a >> b; 
   	cout << setprecision(9) << (a - b) / (double) a * 100 << "\n";
}
