Мерења

import java.util.HashMap;
import java.util.Scanner;


public class Merenja {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);


        int n = Integer.parseInt(scanner.nextLine());

        HashMap<String, String> hashMap = new HashMap<>();


        for (int i =0;i<n;i++)
        {
            String [] niza = scanner.nextLine().split(" ");

            String ime = niza[0];
            String merenja = niza[1];

            if (hashMap.containsKey(ime))
            {
                if (!hashMap.get(ime).contains(merenja))
                    hashMap.put(ime, hashMap.get(ime) + " " + merenja);
            }
            else

            hashMap.put(ime,merenja);


        }

        String key = scanner.nextLine();



        String merenja = hashMap.get(key).replaceAll(",",".");

        String [] broevi = merenja.split(" ");

        int sredina = broevi.length;

        double sum =0;

        for (int i=0;i<broevi.length;i++)
        {
            sum+=Double.parseDouble(broevi[i]);
        }

        System.out.println(sum/sredina);






    }
}

/*
5
        Karposh 5,2
        Chair 3,11
        Centar 2,23
        Karposh 1,7
        Karposh 2,67
        Karposh
        3.19*/