package Yukicoder

import java.math.BigDecimal

/**
 * Created by hichikawa on 2015/11/12.
 */
fun main(args: Array<String>) {
    fun readLineLongArray(): List<Long> {
        val str = readLine() as String
        val arrStr = str.split(".")
        val ret = arrStr.map { it.toLong() }
        return ret
    }

    fun readLineLong(): Long {
        val str = readLine() as String
        return str.toLong()
    }

    fun readLineInt(): Int {
        val str = readLine() as String
        return str.toInt()
    }


    fun readLineDouble(): Double {
        val str = readLine() as String
        return str.toDouble()
    }

    fun readLineIntArray() : List<Int> {
        val str = readLine() as String
        val arrStr = str.split(" ")
        val ret = arrStr.map { it.toInt() }
        return ret
    }

    fun readLineDoubleArray(): List<Double> {
        val str = readLine() as String
        val arrStr = str.split(".")
        val ret = arrStr.map { it.toDouble() }
        return ret
    }
    val num = readLineInt()
    var list = Array(num, {Array<Long>(2, {0})})
    for (i in 0..(num-1)) {
        val str = readLine() as String
        if (str.indexOf(".") != -1) {
            val plmi : Int = if (str.get(0) == '-') -1 else 1
            val arrStr = str.split("\\.")
            val tmp = arrStr.map { it.toLong() }
            list[i][0] = tmp[0]
            list[i][1] = tmp[1] * Math.pow(10.toDouble(), (10-arrStr[1].length).toDouble()).toLong() * plmi
        } else {
            list[i][0] = str.toLong()
        }
    }
    var ans1 : Long = 0.toLong()
    var ans2 : Long = 0.toLong()
    for (item in list) {
        ans1 += item[0]
        ans2 += item[1]
    }
//    println(ans1)
//    println(ans2)
    ans1 += ans2 / 10000000000
    ans2 = ans2 % 10000000000
//    println(ans1)
//    println(ans2)
    if (ans1 >= 0 && ans2 > 0) {
        println(ans1.toString() + "." + java.lang.String.format("%010d",ans2))
    } else if (ans1 < 0 && ans2 < 0) {
        println(ans1.toString() + "." + java.lang.String.format("%010d",ans2*-1))
    } else if (ans1 > 0 && ans2 < 0) {
        println((ans1-1).toString() + "." + java.lang.String.format("%010d",(10000000000+ans2)))
    } else if (ans1 < 0 && ans2 > 0) {
        println((ans1+1).toString() + "." + java.lang.String.format("%010d",(10000000000-ans2)))
    } else if (ans1 == 0.toLong() && ans2 < 0) {
        println("-" + (ans1).toString() + "." + java.lang.String.format("%010d",(ans2*-1)).toString())
    } else if (ans2 == 0.toLong()) {
        println(ans1.toString() + "." + java.lang.String.format("%010d",ans2))
    }
}