public class Solution { public static void main(String[] args) throws IOException { BufferedReader bufferedReader = new BufferedReader(new FileReader(args[0])); String lines; HashMap<String,Double> hashMap = new HashMap<>(); while((lines=bufferedReader.readLine())!=null){ String[] array = lines.split("\\s"); if(!hashMap.containsKey(array[0])){ hashMap.put(array[0],Double.parseDouble(array[1])); } else hashMap.replace(array[0],Double.parseDouble(array[1])+ hashMap.get(array[0])); } bufferedReader.close(); hashMap.entrySet().stream().sorted(Map.Entry.comparingByValue()).forEach(e->System.out.println(e.getKey()+" "+e.getValue())); } }