#include<bits/stdc++.h>
using namespace std;

int main(){
    int a,b;

    cin >> a >> b;
    if(a!=b) printf("%.10f\n", sqrt((a>b)?a*a-b*b:b*b-a*a));
    else printf("%.10f\n", sqrt((a*a+b*b)));

    return 0;
}