import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int l = Math.max(a,b);
        int m = Math.min(a,b);
        double c = Math.sqrt(l*l-m*m);
        System.out.println(c);
    }
}