#include using namespace std; using ll = long long; using P = pair; using T = tuple; #define al(a) a.begin(), a.end() #define ral(a) a.rbegin(), a.rend() #define sz(a) (int)a.size() #define rep(i, n) for (int i = 0; i < (n); ++i) #define rrep(i, n) for (int i = 1; i <= (n); ++i) #define drep(i, n) for (int i = (n)-1; i >= 0; --i) #define db(a, b) cout << #a << ": " << a << " " << #b << ": " << b << endl; int main() { int a, b; cin >> a >> b; if (a < b) swap(a, b); double ans = a * a - b * b; if (a == b) ans = a * a + b * b; cout << fixed << setprecision(15) << sqrt(ans) << endl; return 0; }