#include <iostream>
using namespace std;

int main() {
	double a, b;
	cin >> a >> b;

	int c = a - b;
	cout << (c / a)*100;
	return 0;
}
#include <bits/stdc++.h>

using namespace std;

typedef long long LL;

#define rep(i,n) for(LL i=0;i<(n);i++)

int main()
{
    double a, b;

    cin >> a >> b;

    b = a - b;

    a = b/a;
    a *= 100;

    printf("%.10lf",a);

    return 0;
}