#include <bits/stdc++.h>
using namespace std;

typedef long long   signed int LL;
typedef long long unsigned int LU;

#define incID(i, l, r) for(int i = (l)    ; i <  (r); i++)
#define incII(i, l, r) for(int i = (l)    ; i <= (r); i++)
#define decID(i, l, r) for(int i = (r) - 1; i >= (l); i--)
#define decII(i, l, r) for(int i = (r)    ; i >= (l); i--)
#define inc( i, n) incID(i, 0, n)
#define inc1(i, n) incII(i, 1, n)
#define dec( i, n) decID(i, 0, n)
#define dec1(i, n) decII(i, 1, n)

#define inII(v, l, r) ((l) <= (v) && (v) <= (r))
#define inID(v, l, r) ((l) <= (v) && (v) <  (r))

#define PB push_back
#define EB emplace_back
#define MP make_pair
#define FI first
#define SE second
#define UB upper_bound
#define LB lower_bound
#define PQ priority_queue

#define  ALL(v)  v.begin(),  v.end()
#define RALL(v) v.rbegin(), v.rend()
#define  FOR(i, v) for(auto i =  v.begin(); i !=  v.end(); ++i)
#define RFOR(i, v) for(auto i = v.rbegin(); i != v.rend(); ++i)

template<typename T> bool setmin(T & a, T b) { if(a <= b) { return false; } else { a = b; return true; } }
template<typename T> bool setmax(T & a, T b) { if(b <= a) { return false; } else { a = b; return true; } }
template<typename T> T gcd(T a, T b) { return (b == 0 ? a : gcd(b, a % b)); }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }

template<typename T> ostream & operator<<(ostream & os, const vector<T> & v) {
	os << "[";
	FOR(it, v) {
		if(it != v.begin()) { os << ", "; }
		os << *it;
	}
	os << "]";
	return os;
}
template<typename F, typename S> ostream & operator<<(ostream & os, const pair<F, S> & p) {
	os << "<" << p.FI << ", " << p.SE << ">";
	return os;
}

// ---- ----

int n;
LL ans_d, ans_e;

int main() {
	cin >> n;
	inc(q, n) {
		string s;
		cin >> s;
		
		bool flag = false;
		inc(i, s.size()) {
			if(s[i] == '.') { flag = true; }
		}
		if(! flag) { s += "."; }
		s += "0000000000";
		
		flag = false;
		LL d = 0, e = 0, k = 0;
		inc(i, s.size()) {
			if(s[i] == '-') { continue; }
			if(s[i] == '.') { flag = true; continue; }
			if(! flag) {
				d *= 10;
				d += s[i] - '0';
			} else {
				e *= 10;
				e += s[i] - '0';
				k++;
				if(k == 10) { break; }
			}
		}
		int sign = (s[0] == '-' ? -1 : 1);
		ans_d += sign * d;
		ans_e += sign * e;
		// cout << sign * d << ", " << sign * e << endl;
		// printf("%10lld. %+011lld\n", sign * d, sign * e);
	}
	
	// cout << ans_d << '.' << ans_e << endl;
	
	LL p = 10000000000LL;
	while(ans_e < 0) {
		ans_d--;
		ans_e += p;
	}
	while(ans_e >= p) {
		ans_d++;
		ans_e -= p;
	}
	
	if(ans_d < 0 && ans_e > 0) {
		ans_d++;
		ans_e -= p;
	}
	
	// cout << ans_d << '.' << ans_e << endl;
	
	
	if(ans_d < 0 || (ans_d == 0 && ans_e < 0)) {
		cout << "-";
		ans_d *= -1;
		ans_e *= -1;
	}
	printf("%lld.%010lld\n", ans_d, ans_e);
	
	return 0;
}