// includes #include using namespace std; // macros #define pb emplace_back #define mk make_pair #define FOR(i, a, b) for(int i=(a);i<(b);++i) #define rep(i, n) FOR(i, 0, n) #define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--) #define irep(itr, st) for(auto itr = (st).begin(); itr != (st).end(); ++itr) #define irrep(itr, st) for(auto itr = (st).rbegin(); itr != (st).rend(); ++itr) #define all(x) (x).begin(),(x).end() #define sz(x) ((int)(x).size()) #define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end()) #define bit(n) (1LL<<(n)) // functions template bool chmax(T &a, const T &b){if(a < b){a = b; return 1;} return 0;} template bool chmin(T &a, const T &b){if(a > b){a = b; return 1;} return 0;} template istream &operator>>(istream &is, vector &vec){for(auto &v: vec)is >> v; return is;} template ostream &operator<<(ostream &os, const vector& vec){for(int i = 0; i < vec.size(); i++){ os << vec[i]; if(i + 1 != vec.size())os << " ";} return os;} template ostream &operator<<(ostream &os, const set& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const unordered_set& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const multiset& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const unordered_multiset& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const pair &p){os << p.first << " " << p.second; return os;} template ostream &operator<<(ostream &os, const map &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;} template ostream &operator<<(ostream &os, const unordered_map &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;} // types using ll = long long int; using P = pair; using Pli = pair; using Pil = pair; using Pll = pair; using Pdd = pair; using cd = complex; // constants const int inf = 1e9; const ll linf = 1LL << 50; const double EPS = 1e-10; const int mod = 1000000007; const int dx[4] = {-1, 0, 1, 0}; const int dy[4] = {0, -1, 0, 1}; // io struct fast_io{ fast_io(){ios_base::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(20);} } fast_io_; ostream& operator<<(ostream& dest, __int128_t value) { ostream::sentry s(dest); if(s){ __uint128_t tmp = value < 0 ? - value: value; char buf[128]; char *d = end(buf); do{ --d; *d = "0123456789"[tmp % 10]; tmp /= 10; }while(tmp != 0); if(value < 0)--d, *d='-'; int len = end(buf) - d; if(dest.rdbuf()->sputn(d, len) != len){ dest.setstate(ios_base::badbit); } } return dest; } __int128_t to_int128(string s){ __int128_t res = 0; for(size_t i = 0; i < s.size(); i++){ res = res * 10 + (s[i] - '0'); } return res; } int main(int argc, char const* argv[]) { int n; cin >> n; ll t = 0, b = 0; rep(i, n){ string s; cin >> s; string ss = ""; ll ts = 0, tb = 0; bool p = false; rep(j, sz(s)){ if(j == 0 && s[j] == '-')continue; if(s[j] == '.'){ p = true; ts = stol(ss); ss = ""; }else{ ss += s[j]; } } if(p){ while(sz(ss) < 10)ss += "0"; tb = stol(ss); } else ts = stol(ss); if(s[0] == '-'){ ts *= -1; tb *= -1; } t += ts; b += tb; } ll M = 10000000000LL; __int128_t u = t * M + b; M = __int128_t(M); string B = to_string((ll)(u % M)); while(sz(B) < 10)B += "0"; cout << u / M << "." << B << endl; return 0; }