Can anyone help me in this task ?

Question about the task

The richest

Java Core, Level 9, Lesson 11

Under discussion

last condition is not satisfying...

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; import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.TreeMap; import java.util.Set; import java.util.Map.Entry; import java.io.*; /* The richest Calculating salaries Requirements: 1. The program must NOT read data from the console. 2. The program must read the file's contents (use FileReader). 3. The file input stream (FileReader) must be closed. 4. The program should write to the console each name, sorted in ascending order, and the sum of all its values. */ public class Solution { public static void main(String[] args) { try{ FileReader reader = new FileReader(args[0]); BufferedReader br = new BufferedReader(reader); String data = null; String[] dataArray; Map<String, Double> map = new TreeMap<String, Double>(); while((data = br.readLine()) != null){ dataArray = data.split(" "); if(map.containsKey(dataArray[0])){ Double value = map.get(dataArray[0]); value = value + Double.parseDouble(dataArray[1]); map.remove(dataArray[0]); map.put(dataArray[0],value); }else{ dataArray = data.split(" "); map.put(dataArray[0], Double.parseDouble(dataArray[1])); } } /* Map<String, Integer> map = new HashMap<String, Integer>(); map.put("java", 20); map.put("C++", 45); map.put("Java2Novice", 2); map.put("Unix", 67); map.put("MAC", 26); map.put("Why this kolavari", 93);*/ Set<Entry<String, Double>> set = map.entrySet(); List<Entry<String, Double>> list = new ArrayList<Entry<String, Double>>(set); Collections.sort( list, new Comparator<Map.Entry<String, Double>>() { public int compare( Map.Entry<String, Double> o1, Map.Entry<String, Double> o2 ) { return (o2.getValue()).compareTo( o1.getValue() ); } } ); int count = 0; for(Map.Entry<String, Double> entry:list){ /*if(count > 1) break; count++;*/ System.out.println(entry.getKey()); } reader.close(); br.close(); }catch(Exception ex){ } } }

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Ian De Bie Full Stack Developer

21 October 2020, 17:44

i like to keep it simple. it's very straightforward, but please let me know if you have any questions.

package com.codegym.task.task19.task1920;

/*
The richest
*/

import java.io.*;
import java.util.*;

public class Solution {
    public static void main(String[] args) throws IOException {
        Map<String, Double> map = new TreeMap<>();
        try (BufferedReader buff = new BufferedReader(new FileReader(args[0]))) {
            while (buff.ready()) {
                String[] arr = buff.readLine().split("\\s+");
                map.merge(arr[0], Double.parseDouble(arr[1]), Double::sum);
            }
        }
        double max = map.values().stream().max(Double::compareTo).orElse(0.0);
        map.entrySet().stream().filter(f -> f.getValue() == max).forEach(e -> System.out.println(e.getKey()));
    }
}

shovan

Level 22 , Kolkata, india

18 January 2020, 04:20

i have done this....

import java.io.*;
import java.util.*;
/*
The richest

*/

public class Solution {
    public static void main(String[] args) throws Exception {

            BufferedReader br = new BufferedReader(new FileReader(args[0]));
            ArrayList<String> result = new ArrayList<String>();

            String data;
            String[] dataArray;
            Map<String, Double> map = new TreeMap<>();

            while(br.ready()){
                data = br.readLine();
                dataArray = data.split(" ");

                if(map.containsKey(dataArray[0]))
                    map.replace(dataArray[0], map.get(dataArray[0]) + Double.parseDouble(dataArray[1]));
                else
                    map.put(dataArray[0], Double.parseDouble(dataArray[1]));
            }
            double maxValue = Integer.MIN_VALUE;

            for(Map.Entry<String, Double> pair:map.entrySet()){
                if(pair.getValue() > maxValue){
                    maxValue = pair.getValue();
                }
            }
            for(Map.Entry<String, Double> pair:map.entrySet())
            {
                if(pair.getValue() == maxValue || pair.getValue() >= (maxValue - 1))
                {
                    result.add(pair.getKey());
                }
            }
            Collections.sort(result);
            for(String l : result)
            {
                for(Map.Entry<String, Double> pair:map.entrySet())
                {
                    if(l.equals(pair.getKey()))
                    {
                        System.out.println(pair.getKey());
                    }
                }
            }
            br.close();
    }
}

Guadalupe Gagnon

Level 37 , Tampa, United States

24 December 2018, 16:19

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