#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <cmath>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <stdlib.h>
#include <stdio.h>
#include <bitset>
using namespace std;
#define FOR(I,A,B) for(int I = (A); I < (B); ++I)
typedef long long ll;

int main(){
  int a,b;
  cin>>a>>b;
  double c;
  if(a==b)
  {
    c = a * sqrt(2);
  }
  else
  {
    c = sqrt(max(a,b)*max(a,b)-min(a,b)*min(a,b));
  }

  printf("%.08lf\n", c);
  return 0;
}