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Question about the task

The richest

Java Core, Level 9, Lesson 11

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I tried with ouputs it's fine, displays the largerst value(person) but donno what actually i'm missing little hint. :)

The first parameter of the main method is a file name.
Each line of the specified file has the following format:
name value
where [name] is a String and [value] is a double. [name] and [value] are separated by a space.

Find the sum of all the values for each name.
Display in alphabetical order the names with the highest sum.
Separate the names with a space or new line.
Close the streams.

Example input file:
Peterson 0.501 Smith 1.35 Peterson 0.85

Example output:
Peterson

Requirements:

The program must NOT read data from the console.
The program must read the file's contents (use FileReader).
The file input stream (FileReader) must be closed.
The program should output the names with the highest sum to the console.

package com.codegym.task.task19.task1920; /* The richest */ import java.io.BufferedReader; import java.io.FileReader; import java.util.Map; import java.util.TreeMap; public class Solution { public static void main(String[] args)throws Exception { String s = args[0]; BufferedReader br = new BufferedReader(new FileReader(s)); String s1; Map<String,Double> map = new TreeMap<>(); while (br.ready()){ s1= br.readLine(); String[] str = s1.split(" "); double value; //double high=map.get(map.lastKey()); if(map.containsKey(str[0])){ String name = str[0]; value=Double.parseDouble(str[1]); map.put(name,map.get(name)+value); }else { map.put(str[0],Double.valueOf(str[1])); } } String max= null; double high = Integer.MIN_VALUE; for (Map.Entry<String,Double> entry : map.entrySet()) { if (entry.getValue() > high) { high= entry.getValue(); max= entry.getKey(); } } System.out.println(max); br.close(); } }

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Nouser

Level 36 , Germany

29 August 2020, 13:39

If there are several people with the same value then display them all.

dhanush

Level 30 , Chennai, India

31 August 2020, 05:03

I have done by checked several people with same value but i don't know it doesn't print expected result

for (Map.Entry<String, Double> entry : map.entrySet()){
            if(entry.getValue().equals(high)){
                System.out.println(max);
            }
        }

if my input is ->fizz 50 ->cat 50 ->hen 25 ->cat 50 ->fizz 50 it displays the result as fizz fizz

Nouser

Level 36 , Germany

31 August 2020, 06:44

solution

instead of printing max output entry.getKey(). max still holds the first key having the max value. Line 33 is problematic as well cause you're working with double values. And instead of finding the max yourself you could use Collections functionality:

//get max value in map
Double high = Collections.max(map.values());

dhanush

Level 30 , Chennai, India

31 August 2020, 09:01

Yeah really cool to use these methods. I just just by changing the variable high and it passed the validation. Thank you Nouser. :)