import java.io.*; import java.math.*; class Main{ static final PrintWriter out=new PrintWriter(System.out); public static void main(String[] args) throws IOException{ BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); String line=""; BigDecimal x=new BigDecimal("0.0"); while((line=br.readLine())!=null&&!line.isEmpty()){ BigDecimal y=new BigDecimal(line); x=x.add(y); } x=x.setScale(10,RoundingMode.HALF_UP); out.printf("%.3f",x); out.flush(); } }