#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define endl '\n' #define ALL(v) (v).begin(), (v).end() #define RALL(v) (v).rbegin(), (v).rend() #define UNIQ(v) (v).erase(unique((v).begin(), (v).end()), (v).end()) typedef long long ll; typedef long double ld; typedef pair P; typedef complex comp; typedef vector< vector > matrix; struct pairhash { public: template size_t operator()(const pair &x) const { size_t seed = hash()(x.first); return hash()(x.second) + 0x9e3779b9 + (seed<<6) + (seed>>2); } }; const int inf = 1e9 + 9; const ll mod = 1e9 + 7; const double eps = 1e-8; const double pi = acos(-1); int n; string a[110]; string solve() { ll d[n], s[n]; bool neg[n]; for (int i = 0; i < n; i++) { string t = ""; int j = 0; while (j < a[i].size() && a[i][j] != '.') j++; if (a[i][0] == '-') { d[i] = stoll(a[i].substr(1, j)); neg[i] = true; } else { d[i] = stoll(a[i].substr(0, j)); neg[i] = false; } if (j == a[i].size()) { s[i] = 0; } else { string temp = a[i].substr(j+1, a[i].size()); while (temp.size() < 10) temp += '0'; s[i] = stoll(temp); } } ll res[2] = {0LL, 0LL}; for (int i = 0; i < n; i++) { res[0] += (neg[i]?-1:1)*d[i]; res[1] += (neg[i]?-1:1)*s[i]; } ll m = 1e10; stringstream ss; if ((res[0] <= 0 && res[1] <= 0) || (res[0] >= 0 && res[1] >= 0)) { string sig = ""; if (res[0] < 0) { sig += '-'; res[0] *= -1; res[1] *= -1; } ss << sig; res[0] += res[1] / m; res[1] %= m; } else { if (res[0] >= 0) { res[0] -= res[1] / m; res[1] %= m; res[0]--; res[1] = m - res[1]; } else { res[0] += res[1] / m; res[1] %= m; } } string q = to_string(res[1]); ss << res[0] << "."; for (int i = 0; i < 10-(int)q.size(); i++) { ss << 0; } ss << q; return ss.str(); } void input() { cin >> n; for (int i = 0; i < n; i++) cin >> a[i]; } int main() { ios::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(15); input(); cout << solve() << endl; }