#include <iostream>
using namespace std;

int main()
{
  double x,y;
  cin >> x >> y;
  long double z = ((x-y)/x)*100;
  cout << z << endl;
  return 0;
}
#include <bits/stdc++.h>
using namespace std;

#define 	 int long long
#define 	 pb push_back
#define 	 mp make_pair
#define 	 sz(v) ((int)(v).size()) 
#define 	 endl '\n'
#define 	 IO ios::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define    	 sortA(v)          sort(v.begin(), v.end())
#define   	 sortD(v)          sort(v.rbegin(), v.rend())
#define 	 all(x)            (x).begin(),(x).end()
#define	 	 gcd(a,b) 	       __gcd(a,b)
#define 	 rep(i,a,b) 	   for(int i=a;i<b;i++)
#define 	 repd(i,a,b) 	   for(int i=b-1;i>=a;i--)
#define 	 trav(a,x) 		   for(auto &a:x)
typedef vector<int> vi;

// const int N = 1e5 + 5;

void solve(){
	float a,b;
	cin >> a >> b;
	cout << ((a-b)/a)*100 << endl;
}

int32_t main()
{
	IO;
	// freopen("input.txt", "r", stdin);
	// freopen("output.txt", "w", stdout);	
	int t = 1;
	// cin >> t;
	while (t--)
	{
		solve();
	}
    return 0;
}
