В IntelliJ IDEA все работает
package com.javarush.task.task08.task0817;
import java.util.HashMap;
import java.util.Map;
/*
Нам повторы не нужны
*/
public class Solution {
public static HashMap<String, String> createMap() {
HashMap<String, String> map = new HashMap<>();
map.put("a","a");
map.put("b","a");
map.put("c","b");
map.put("d","c");
map.put("e","a");
map.put("f","d");
map.put("g","e");
map.put("h","f");
map.put("i","a");
map.put("j","g");
return map;
}
public static HashMap<String, String> removeTheFirstNameDuplicates(HashMap<String, String> map) {
HashMap<String, String> copy = new HashMap<String, String>(map);
for (Map.Entry<String, String> pair : copy.entrySet()) {
String s = pair.getValue();
int n = 0;
for (Map.Entry<String, String> pair1 : copy.entrySet()) {
if (pair1.getValue().equals(s))
n++;
}
if (n > 1)
removeItemFromMapByValue(map, s);
}
return map;
}
public static void removeItemFromMapByValue(HashMap<String, String> map, String value) {
HashMap<String, String> copy = new HashMap<String, String>(map);
for (Map.Entry<String, String> pair : copy.entrySet()) {
if (pair.getValue().equals(value))
map.remove(pair.getKey());
}
}
public static void main(String[] args) {
/*for (Map.Entry<String, String> pair : removeTheFirstNameDuplicates(createMap()).entrySet()) {
System.out.println(pair.getValue());
}*/
}
}