Migratory Bird Problem hackerRank

 Given an array of bird sightings where every element represents a bird type id, determine the id of the most frequently sighted type. If more than 1 type has been spotted that maximum amount, return the smallest of their ids.

Example

There are two each of types  and , and one sighting of type . Pick the lower of the two types seen twice: type .

Function Description

Complete the migratoryBirds function in the editor below.

migratoryBirds has the following parameter(s):

• int arr[n]: the types of birds sighted

Returns

• int: the lowest type id of the most frequently sighted birds

Input Format

The first line contains an integer, , the size of .
The second line describes  as  space-separated integers, each a type number of the bird sighted.

Constraints

• It is guaranteed that each type is , , , , or .

import java.io.*;

import java.math.*;

import java.security.*;

import java.text.*;

import java.util.*;

import java.util.concurrent.*;

import java.util.function.*;

import java.util.regex.*;

import java.util.stream.*;

import static java.util.stream.Collectors.joining;

import static java.util.stream.Collectors.toList;

class Result {

    /*

     * Complete the 'migratoryBirds' function below.

     *

     * The function is expected to return an INTEGER.

     * The function accepts INTEGER_ARRAY arr as parameter.

     */

    public static int migratoryBirds(List<Integer> arr) {

    // Write your code here

    TreeMap<Integer,Integer> map= new TreeMap<>();

   

    for(int i:arr)

    {

        map.put(i, map.getOrDefault(i, 0)+1);

    }

   

    int count=0;

    int mostFrequentBird = -1;

    for(Map.Entry<Integer,Integer> entry:map.entrySet())

    {

        int key=entry.getKey();

        int value=entry.getValue();

       

        if(value>count)

        {

            count=value;

            mostFrequentBird=key;

           

        }

    }

   

return mostFrequentBird;

    }

}

public class Solution {

    public static void main(String[] args) throws IOException {

        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        int arrCount = Integer.parseInt(bufferedReader.readLine().trim());

        List<Integer> arr = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))

            .map(Integer::parseInt)

            .collect(toList());

        int result = Result.migratoryBirds(arr);

        bufferedWriter.write(String.valueOf(result));

        bufferedWriter.newLine();

        bufferedReader.close();

        bufferedWriter.close();

    }

}