Cannot find what is wrong

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Hey guys, Could you please take a look what can be wrong here. I get correct output but still cannot pass the test. Thanks, Roman

package com.codegym.task.task18.task1803; import java.io.BufferedReader; import java.io.FileInputStream; import java.io.InputStream; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.Collections; /* Most frequent bytes */ public class Solution { public static void main(String[] args) throws Exception { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String name = reader.readLine(); InputStream input = new FileInputStream(name); ArrayList<Integer> arr = new ArrayList<Integer>(); while (input.available() > 0) { int data = input.read(); arr.add(data); } input.close(); Collections.sort(arr); int n = arr.size(); //System.out.println(arr); mostFrequent(arr, n); } public static int mostFrequent(ArrayList<Integer> arr, int n) { ArrayList<Integer> curr = new ArrayList<Integer>(); int max_count = 1, res = arr.get(0); int curr_count = 1; for (int i = 1; i < n; i++) { if (arr.get(i) == arr.get(i - 1)) curr_count++; else { if (curr_count > max_count) { /*if (curr_count > 1) curr.add(arr.get(i - 1));*/ //max_count = curr_count; res = arr.get(i - 1); } curr_count = 1; } } // If last element is most frequent /*if (curr_count > max_count) { max_count = curr_count; res = arr.get(n - 1); //curr.add(arr.get(n - 1)); }*/ /*for (Integer t : curr) { System.out.print(t + " "); }*/ System.out.print(res + " "); return res; } }

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Nouser

Level 36 , Germany

15 March 2021, 10:58

you do not display all most frequently repeated bytes but only one

Roman Grygorczuk

Level 19 , Cracow, Poland

15 March 2021, 16:16

when I display all of them, I mean three, it says that I'm displaying all the values instead of the frequent ones. The code which does it is commented

Roman Grygorczuk

Level 19 , Cracow, Poland

15 March 2021, 16:17

ok, so I should definitely display all frequent values? like we have [10, 10, 101, 101, 105, 115, 116, 116, 116, 120] and system should display 10, 101, 116, right?

Nouser

Level 36 , Germany

15 March 2021, 17:01

116, it occurs 3 times as far as I can see example: AABBC => 65 66 I used a map, key is the byte. For each read byte -> if the byte (key) doesn't exist, I added it with avalue of 1 if the key is already in the map -> value++ when doing that you can determin the max then a loop over the map and print all bytes with value == max

Roman Grygorczuk

Level 19 , Cracow, Poland

16 March 2021, 22:25

I did like you said but still nothing. Can you please check it?

public static void main(String[] args) throws Exception {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String name = reader.readLine();

        InputStream input = new FileInputStream(name);
        HashMap<Integer, Integer> nums = new HashMap<Integer, Integer>();

        int value = 1;
        int max_value = 1;

        while (input.available() > 0) {
            int data = input.read();
            if (!nums.containsKey(data)){
                nums.put(data,value);
            } else {
                nums.put(data,value++);
                if (value > max_value){
                    max_value = value - 1;
                }
            }
        }
        input.close();

        for (Map.Entry<Integer, Integer> entry : nums.entrySet()) {
            if (entry.getValue().equals(max_value)) {
                System.out.print(entry.getKey());
                break;
            }
        }
    }

Roman Grygorczuk

Level 19 , Cracow, Poland

16 March 2021, 22:27

break is no needed there, anyway it does not change anything so far

Nouser

Level 36 , Germany

17 March 2021, 06:47

solution

OK, getting close ;) as you have already removed the break, you just need to add a space to the output (as all of the most frequently repeated bytes from the file should be displayed, separated by spaces). Then there is a problem with adding the values to the map. When no key exists, then add 1 to the map. Make that visible. Hardcode that 1 or make value a constant. Inside the else cluause. Here you use value again and each time you access that else clause, you rise it again. Means, that variable is used for all bytes. If eg. a occurs 2 tiimes at the moment, and then you need to increase value for byte b to 3 then the next time a occurs you rise value to 4, but it sould be 3. That won't work. You need to read the vlue from the map for that key.

int newValue = nums.get(data) + 1;
nums.put(data, newValue);
if (newValue > max_value) {
    max_value = newValue;
}

Fingers crossed, that should be the solution.