can any one please explain

Question about the task

We don't need repeats

Java Syntax, Level 8, Lesson 8

Under discussion

I think my code is corect but why task condition is not met

Create a Map<String, String> and add ten entries that represent (last name, first name) pairs.
Remove people with the same first name.

Requirements:

The program should not display text on the screen.
The program should not read values from the keyboard.
The createMap() method must create and return a HashMap that has (String, String) elements and contains 10 entries.
The removeFirstNameDuplicates() method must remove from the map all people who have the same first name.
The removeFirstNameDuplicates() method must call the removeItemFromMapByValue() method.

package com.codegym.task.task08.task0817; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.ArrayList; /* We don't need repeats */ public class Solution { public static HashMap<String, String> createMap() { //write your code here HashMap<String,String> map = new HashMap<String,String>(); map.put("a","nitin"); map.put("b","subham"); map.put("c","nitin"); map.put("d","nitin"); map.put("e","nitin"); map.put("f","priyam"); map.put("g","subham"); map.put("h","nitin"); map.put("i","pritam"); map.put("j","nitin"); return map; } public static void removeFirstNameDuplicates(Map<String, String> map) { //write your code here ArrayList<String> NewList = new ArrayList<String>(); Iterator<Map.Entry<String,String>> iterator = map.entrySet().iterator(); while(iterator.hasNext()) { Map.Entry<String,String> pair = iterator.next(); if(!NewList.contains(pair.getValue())) { NewList.add(pair.getValue()); } else { removeItemFromMapByValue(map,pair.getValue()); removeFirstNameDuplicates(map); break; } } } public static void removeItemFromMapByValue(Map<String, String> map, String value) { Iterator<Map.Entry<String,String>> itr = map.entrySet().iterator(); while(itr.hasNext()) { Map.Entry<String,String> val = itr.next(); if(val.getValue().equals(value)) { map.remove(val.getKey()); } } } public static void main(String[] args) { } }

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Przemysław Dr

Level 20 , Tricity, Poland

1 August 2019, 20:29

Try this code in main method and You will see if it works: HashMap<String, String> noDuplicates = createMap(); removeFirstNameDuplicates(noDuplicates); System.out.println(noDuplicates); You are trying do solve this by recursion therefore I think that You don't need an Iterator in removeFirstNameDuplicates method. This solution was descriped here.