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package commonCharacter;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.*;

public class MostCommonCharacters {
    public static void main(String[] args) {
        String characters = String.valueOf(fileReader("countchar.txt"));
        getTwoMostCommonCharacters(characters);
    }

    private static void getTwoMostCommonCharacters(String fileName){
        HashMap<Character, Integer> charCountMap = new HashMap<>();

        char[] charArray = fileName.replaceAll("\\s+", "").toCharArray();
        for (char temp : charArray) {

            if (charCountMap.containsKey(temp)) {
                charCountMap.put(temp, charCountMap.get(temp) + 1);
            } else {
                charCountMap.put(temp, 1);
            }
        }
        Collection<Integer> values = charCountMap.values();

        ArrayList<Integer> listOfValues = new ArrayList<>(values);

        Collections.sort(listOfValues);

        List<Integer> highValue = List.of(listOfValues.get(listOfValues.size()-1));
        List<Integer> secondHighValue = List.of(listOfValues.get(listOfValues.size()-2));

        String formattedString1 = highValue.toString()
                .replace(",", "")
                .replace("[", "")
                .replace("]", "")
                .trim();
        String formattedString2 = secondHighValue.toString()
                .replace(",", "")
                .replace("[", "")
                .replace("]", "")
                .trim();

        System.out.println(getKeyByValue(charCountMap,listOfValues.get(listOfValues.size()-1)) + ": " + formattedString1);
        System.out.println(getKeyByValue(charCountMap,listOfValues.get(listOfValues.size()-2)) + ": " + formattedString2);

    }
    public static <T, E> T getKeyByValue(Map<T, E> map, E value) {
        for (Map.Entry<T, E> entry : map.entrySet()) {
            if (Objects.equals(value, entry.getValue())) {
                return entry.getKey();
            }
        }
        return null;
    }

    private static List<String> fileReader(String fileName) {
        Path filePath = Paths.get(fileName);
        try {
            List<String>fileline= Files.readAllLines(filePath);
            return fileline;
        } catch (IOException e) {
            System.out.println("File does not exist!");
            return null;
        }


    }
}