#include using namespace std; typedef long long ll; typedef vector VI; typedef vector VVI; typedef vector VL; typedef vector VVL; typedef pair PII; #define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i) #define REP(i, n) FOR(i, 0, n) #define ALL(x) x.begin(), x.end() #define MOD 1000000007 #define INF (1LL<<25) //33554432 #define PI 3.14159265359 #define EPS 1e-12 //#define int ll signed main(void) { int a, b; cin >> a >> b; if(a == b) { cout << fixed << setprecision(15) << a*sqrt(2) << endl; return 0; } if(b > a) swap(a, b); cout << fixed << setprecision(15) << sqrt(a*a-b*b) << endl; return 0; }