import java.util.ArrayList;
import java.util.HashMap;

class Fletting {

    static String[] ulikeNavn = {
        "peter",
        "daniel",
        "oda",
        "frank"
    };

    static HashMap<Character, Integer> lagHashMap(String navn) {
        HashMap<Character, Integer> hm = new HashMap<Character, Integer>();

        for (int i = 0; i<navn.length(); i++) {
            char bokstav = navn.charAt(i); 
            hm.put(bokstav, 1);
        }

        return hm;
    } 

    static HashMap<Character, Integer> flett(HashMap<Character, Integer> hm1, HashMap<Character, Integer> hm2) {

        for (char b : hm1.keySet()) {
            if (hm2.containsKey(b)) {
                int nyVerdi = hm1.get(b) + hm2.get(b);
                hm2.put(b, nyVerdi);
            }
            else {
                hm2.put(b, hm1.get(b));
            }
        }

        return hm2;
    }

    static ArrayList<HashMap<Character, Integer>> hashMapBeholder = new ArrayList<>();

    public static void main(String[] args) {
        HashMap<Character, Integer> testHm;

        for (String navn : ulikeNavn) {
            testHm = lagHashMap(navn);
            hashMapBeholder.add(testHm);
        }

        testHm = flett(hashMapBeholder.get(2), hashMapBeholder.get(1));

        for (char b : testHm.keySet()) {
            System.out.println(b + " : " + testHm.get(b));
        }


 
    }
}