#define _USE_MATH_DEFINES #include "bits/stdc++.h" using namespace std; #define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i)) #define rep(i,j) FOR(i,0,j) #define each(x,y) for(auto &(x):(y)) #define mp make_pair #define MT make_tuple #define all(x) (x).begin(),(x).end() #define debug(x) cout<<#x<<": "<<(x)<<endl #define smax(x,y) (x)=max((x),(y)) #define smin(x,y) (x)=min((x),(y)) #define MEM(x,y) memset((x),(y),sizeof (x)) #define sz(x) (int)(x).size() #define RT return using ll = long long; using pii = pair<int, int>; using vi = vector<int>; using vll = vector<ll>; void solve() { double r, d; cin >> r >> d; cout << sqrt(d*d - r*r) << endl; } int main() { ios::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(15); solve(); return 0; }