[해커랭크] Picking Numbers

Given an array of integers, find the longest subarray where the absolute difference between any two elements is less than or equal to .

Example

 

There are two subarrays meeting the criterion:  and . The maximum length subarray has  elements.

Function Description

Complete the pickingNumbers function in the editor below.

pickingNumbers has the following parameter(s):

• int a[n]: an array of integers

Returns

• int: the length of the longest subarray that meets the criterion

Input Format

The first line contains a single integer , the size of the array .
The second line contains  space-separated integers, each an .

Constraints

•  
•  
• The answer will be .

Sample Input 0

6
4 6 5 3 3 1

Sample Output 0

3

Explanation 0

We choose the following multiset of integers from the array: . Each pair in the multiset has an absolute difference  (i.e.,  and ), so we print the number of chosen integers, , as our answer.

Sample Input 1

6
1 2 2 3 1 2

Sample Output 1

5

Explanation 1

We choose the following multiset of integers from the array: . Each pair in the multiset has an absolute difference  (i.e., , , and ), so we print the number of chosen integers, , as our answer.

 

 

 

 

 

풀이

그저 cost 리스트에 숫자의 개수를 세고,

(n과 n+1) 두개의 숫자의 개수가 많은 경우를 구하면 끝.

 

늘 느끼는거지만, 어렵게 생각하지 말자.

테케는 수없지 많겠지만, 답은 정해져 있을지어다.

 

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 'pickingNumbers' function below.

     *

     * The function is expected to return an INTEGER.

     * The function accepts INTEGER_ARRAY a as parameter.

     */

    public static int pickingNumbers(List<Integer> a) {

    // Write your code here

   

        if(a.size() == 1){

            return 1;

        }

       

        int[] cost = new int[101];

        for(int n : a){

            cost[n]++;

        }

       

        int max = Integer.MIN_VALUE;

        for(int i=0; i<a.size()-1; i++){

            int tempSum = cost[i]+cost[i+1];

            max = (max < tempSum) ? tempSum : max;

        }

       

        return max;

    }

}

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 n = Integer.parseInt(bufferedReader.readLine().trim());

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

            .map(Integer::parseInt)

            .collect(toList());

        int result = Result.pickingNumbers(a);

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

        bufferedWriter.newLine();

        bufferedReader.close();

        bufferedWriter.close();

    }

}