use std::collections::{HashMap, HashSet};

use proconio::marker::Chars;

fn main() {
    proconio::input! {
        n: u32,
        mut a: [String;n],
    }
    let a = a
        .into_iter()
        .map(|s| {
            let s = s.split('.').collect::<Vec<_>>();
            if s.len() == 1 {
                [
                    s[0].parse::<i128>().unwrap() + 1,
                    -10000000000,
                ]
            } else {
                [
                    s[0].parse::<i128>().unwrap(),
                    s[1].parse::<i128>().unwrap()
                        * (10i128).pow(10 - s[1].len() as u32)
                        * if s[0].starts_with('-') { -1 } else { 1 },
                ]
            }
        })
        .collect::<Vec<_>>();
    for a in a.iter() {
        eprintln!("{a:?}");
    }
    let x = a.iter().map(|x| x[0]).sum::<i128>();
    let y = a.iter().map(|x| x[1]).sum::<i128>();
    let x = x + y / 10000000000;
    let y = y % 10000000000;
    println!("{}.{:010}", x, y.abs());
}