package string;

import java.util.*;

import java.util.stream.Collectors;

import java.util.stream.Stream;

import static java.lang.String.valueOf;

import static java.util.stream.Collectors.*;

//Write a program to the least occurring character from a given string.

public class Question28 {

public static void main(String[] args) {

String word = "aHHellooooee";

Map<Object, Set<String>> map = retrieveSetMap(word);

map.forEach((k,v)-> System.out.printf("Count: %s Values: %s\n",k,v));

System.out.println(map.values().stream());

}

private static Map<Object, Set<String>> retrieveSetMap(String word) {

return Stream.of(word.split(""))

.collect(groupingBy(each -> countFrequencyOfLetter(word, valueOf(each)), toSet()));

}

public static long countFrequencyOfLetter(String word, String letter) {

return Arrays.stream(word.split("")).filter(each -> each.equals(letter)).count();

}

}