#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <map>
#include <set>
#include <algorithm>
#include <functional>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cctype>
#include <string>
#include <cstring>

using namespace std;

typedef long long ll;

bool compare(const long double a, const long double b) {
  return fabsl(a) < fabsl(b);
}

int main() {
  int n;
  cin >> n;
  vector<string> a, b;
  int ans[100] = {0}, bbb[100] = {0};
  for (int i = 0; i < n; i++) {
    string s;
    cin >> s;
    if (s[0] == '-') {
      b.push_back(s.substr(1));
    }else {
      a.push_back(s);
    }
  }

  for (int i = 0; i < a.size(); i++) {
    bool ok = false;
    for (int j = 0; j < a[i].size(); j++) {
      if (a[i][j] == '.') {
        ok = true;
        string t = "";
        for (int k = 0; k < 50-j; k++) t += "0";
        a[i] = t+a[i].substr(0, j)+a[i].substr(j+1);
        int n = a[i].size();
        for (int k = 0; k < 100-n; k++) a[i] += "0";
      }
    }
    if (!ok) {
      int n = a[i].size();
      string t = "";
      for (int j = 0; j < 50-n; j++) t += "0";
      a[i] = t+a[i];
      n = a.size();
      for (int j = 0; j < 100-n; j++) a[i] += "0";
    }
  }
  for (int i = 0; i < b.size(); i++) {
    bool ok = false;
    for (int j = 0; j < b[i].size(); j++) {
      if (b[i][j] == '.') {
        ok = true;
        string t = "";
        for (int k = 0; k < 50-j; k++) t += "0";
        b[i] = t+b[i].substr(0, j)+b[i].substr(j+1);
        int n = b[i].size();
        for (int k = 0; k < 100-n; k++) b[i] += "0";
      }
    }
    if (!ok) {
      int n = b[i].size();
      string t = "";
      for (int j = 0; j < 50-n; j++) t += "0";
      b[i] = t+b[i];
      n = b.size();
      for (int j = 0; j < 100-n; j++) b[i] += "0";
    }

  }

  int c = 0;
  for (int i = 0; i < a.size(); i++) {
    c = 0;
    for (int j = 99; j >= 0; j--) {
      int t = ans[j];
      ans[j] = (ans[j]+(a[i][j]-'0')+c)%10;
      c = (t+(a[i][j]-'0')+c)/10;
    }
  }
  for (int i = 0; i < b.size(); i++) {
    c = 0;
    for (int j = 99; j >= 0; j--) {
      int t = bbb[j];
      bbb[j] = (bbb[j]+(b[i][j]-'0')+c)%10;
      c = (t+(b[i][j]-'0')+c)/10;
    }
  }

  int p;
  for (int i = 0; i < 99; i++) {
    if (ans[i] > 0) {
      p = i;
      break;
    }
  }

  // for (int i = 0; i < 100; i++) cout << ans[i];
  // cout << endl;
  // for (int i = 0; i < 100; i++) cout << bbb[i];
  // cout << endl;
  bool ok = false;
  for (int i = 0; i < 100; i++) {
    if (ans[i] < bbb[i]) {
      ok = true;
    }else if (ans[i] > bbb[i]) {
      break;
    }
  }
  if (ok) {
    for (int i = 0; i < 100; i++) {
      int t = ans[i];
      ans[i] = bbb[i];
      bbb[i] = t;
    }
  }
  
  bool minus = false;
  c = false;
  for (int i = 99; i >= 0; i--) {
    if (ans[i]-bbb[i]-c < 0) {
      if (i <= p) {
        minus = true;
        ans[i] = bbb[i]-(ans[i]-c);
        c = false;
      }else {
        ans[i] = 10-(bbb[i]-(ans[i]-c));
        c = true;
      }
    }else {
      ans[i] = ans[i]-bbb[i]-c;
      c = false;
    }
  }

  int l, r;
  for (int i = 0; i < 100; i++) {
    if (ans[i] > 0) {
      l = i;
      break;
    }
  }
  for (int i = 100; i >= 0; i--) {
    if (ans[i] > 0) {
      r = i;
      break;
    }
  }

  if (!(minus && ok) && (minus || ok)) cout << "-";
  if (l == 50) {
    cout << "0";
  }
  for (int i = l; i <= r; i++) {
    if (i == 50) {
      cout << "." << ans[i];
    }else {
      cout << ans[i];
    }
  }
  if (r < 50) {
    for (int i = 0; i < 49-r; i++) cout << "0";
    cout << ".";
    for (int i = 0; i < 10; i++) cout << "0";
  }else {
    for (int i = 0; i < 10-((r+1)-50); i++) cout << "0";
  }
  cout << endl;
}