#include using namespace std; #define _GLIBCXX_DEBUG #define rep(i, from, to) for (ll i = from; i < (to); ++i) #define mp(x,y) make_pair(x,y) #define all(x) (x).begin(),(x).end() #define sz(x) (int)(x).size() #define pb push_back using ll = long long; using ld=long double; using vin=vector; using vvin=vector; using vll=vector; using vvll=vector; using vst=vector; using P = pair; const int inf=1e9+7; const ll INF=9e18; const long double PI = acos(-1.0); template bool chmin(T &a, const T& b){if(a > b){a = b;return true;}return false;} template bool chmax(T &a, const T& b){if(a < b){a = b;return true;}return false;} template inline void Yes(T condition){ if(condition) cout << "Yes" << endl; else cout << "No" << endl; } template inline void YES(T condition){ if(condition) cout << "YES" << endl; else cout << "NO" << endl; } const int dx[4] = { 1, 0, -1, 0 }; const int dy[4] = { 0, 1, 0, -1 }; int main(){cout<>n; vector x(n); rep(i,0,n)cin>>x[i]; ld sum=0; rep(i,0,n){ sum+=sqrt(x[i]); cout<