#include <stdio.h>
#include <math.h>
int min(int a,int b){
  return a<b?a:b;
}
int max(int a,int b){
  return a<b?b:a;
}
double min2(double a,double b){
  return a<b?a:b;
}
int main(){
  int a,b;
  int l1,l2;
  scanf("%d %d",&a,&b);
  if(a==b){
    printf("%lf\n",sqrt(a*a+b*b));
return 0;
  }
  l1=min(a,b);
  l2=max(a,b);
  printf("%.8lf\n",min2(sqrt(l1*l1+l2*l2),sqrt(l2*l2-l1*l1)));
  return 0;
}