[Hackerrank] Arrays

Objective
Today, we will learn about the Array data structure. Check out the Tutorial tab for learning materials and an instructional video.

Task
Given an array, A, of N integers, print A's elements in reverse order as a single line of space-separated numbers.

Example

A = [1, 2, 3, 4]

Print 4 3 2 1. Each integer is separated by one space.

Input Format

The first line contains an integer, N (the size of our array).
The second line contains N space-separated integers that describe array 's elements.

Constraints

• 1 <= N <= 1000
• 1 < A[i] <= 10000, where A[i] is the i(th) integer in the array.

Output Format

Print the elements of array A in reverse order as a single line of space-separated numbers.

Sample Input

4 
1 4 3 2

Sample Output

2 3 4 1

 

---

• N길이의 A라는 공백으로 구분된 배열을 준다.
• 받은 배열을 뒤집어서 출력하여준다.

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;



public class Solution {
    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

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

        List<Integer> arr = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))
            .map(Integer::parseInt)
            .collect(toList());

        Collections.reverse(arr);
        
        for(int num : arr) {
            System.out.print(num + " ");
        }
        


        bufferedReader.close();
    }
}