#include <iostream>
#include <vector>
#include <cmath>
#include <iomanip>
using namespace std;
const long long k = 10;
void make_0(string &a){
  for(int i = 0;i < a.size();i++){
	if(a[i] == '.'){
	  for(int j = a.size() - i;j <= 10;j++){
		a = a + "0";
	  }
	  return;
	}
  }
  a += ".";
  for(int i = 0;i < 10;i++){
	a = a +  "0";
  }
}
string get_d(string a){
  
  string res = "";
  for(int i = 0;i < a.size();i++){
	if(a[i] == '.'){
	  for(int j = i+1;j < a.size();j++){
		res = res + a[j];
	  }
	  break;
	}
  }
  return a[0] == '-' ? "-" + res: res;
}

int main(){
   // string tmp;
   // cin >> tmp;
   // make_0(tmp);
   // cout << tmp << endl;
  
  long long n;
  cin >> n;
  long long ji = 0;
  long long sh = 0;
  for(int i = 0;i < n;i++){
	string a;
	cin >> a;
	make_0(a);
	ji += stoll(a);
	sh += stoll(get_d(a));
  }


  ji+= (long long)(sh/pow(10,10));
  sh = sh%(long long)pow(10,10);
  string sh_s = to_string(sh);
  for(int i = sh_s.size();i < 10;i++){
	sh_s = sh_s + "0";
  }
  cout << ji << "." << sh_s << endl;
  
  return 0;
}