What I m getting wrong?

Question about the task

Rarest bytes

Java Core, Level 8, Lesson 3

Under discussion

Is this what i should display?

package com.codegym.task.task18.task1804; import java.io.BufferedReader; import java.io.FileInputStream; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.Map; /* Rarest bytes */ public class Solution { public static void main(String[] args) throws Exception { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); FileInputStream file = new FileInputStream(reader.readLine()); HashMap<Integer, Integer> map = new HashMap(); while(file.available()>0){ int t1 = file.read(); if(!map.containsKey(t1)){ map.put(t1,1); } else { int t = map.get(t1); map.put(t1,t+1); } } file.close(); ArrayList<Integer> test1 = new ArrayList<>(); int t2=0; for(Map.Entry<Integer, Integer> map2 : map.entrySet()){ t2 = map2.getValue(); test1.add(t2); } Collections.sort(test1); for(int i=0; i < test1.size(); i++) { System.out.print(test1.get(i) + " "); } } }

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Nouser

Level 36 , Germany

4 September 2020, 08:09

working till line 32 (including). In the while loop (line 22) have a min variable after updating the value in the map (that stores the min value: int min = Byte.MAX_VALUE;), like:

if (map.get(t1) < min)
    min = map.get(t1);

Then after line 32 loop over the map and display all keys where the value matches min

dhanush

Level 30 , Chennai, India

4 September 2020, 05:42

You almost got to the point but while you are putting the value in the map inside the if statement that actually didn't work as you expected they ask you to display the rarest number of bytes in the file while you are adding

if(!map.containsKey(t1)){
                map.put(t1,1);
            }
            else {
                int t = map.get(t1);
                map.put(t1,t+1);
            }

line 25 adds the key t1 if not contains in the map and the value also adds but you should count that,say like while the number is in the map then the value should add and the value is counted(increment) how many times the value is added and in the else statement also i think that's for finding the most frequent bytes i don't know actually about that but if you come to rarest byte if not contains means map should add the value and the count should be zero because there is no contained value in the map.

if(map.containsKey(file)){
//map should add the file and count should be incremented
}
else{
//map should add the file and count is assigned
}

you don't need lines 33,34 and 41-44 because you don't want to sort the byte just want to find the rarest bytes in the file. Assign a max value and store the max value of map,inside the for loop iterator check that

if(map.getValue()==max){
//print the key which contains the max value
}