Reverse two input array in java

Question

How can I reverse this code? I thought that I'm using the right way to reverse this array, but it still doesn't work...

I hope someone can help me. tq

so, this is my code :

import java.util.Scanner ;

public class ArrayYear
{
    public static void main (String[] args)
    {
       Scanner in = new Scanner(System.in);
       int[] arr = new int[3];
       int[] year = new int[3];

       //read element into array 
       for (  int i=0 ; i <= arr.length ; i++ )
       {
           arr[i] = in.nextInt() ;  // input value 

            for ( int j=0 ; j<=arr.length/2 ; j++ ){

                  int temp = arr[j];
                  arr[j] = arr[arr.length - i - 1 ];
                  arr[arr.length - i - 1 ] = temp;               
          }   

           year[i]= in.nextInt();

           System.out.println( "ID :" + arr[i] + "("+ year[i] +")" ) ;
       }      
    }
}

note : the array that needed to be reverse is only the first array arr[i]

Answer 1

import java.util.Collections;
import java.util.Scanner;

public class ArrayYear {

    public static void main(String[] args) {

        Scanner in = new Scanner(System. in );
        int[] arr = new int[3];
        int[] year = new int[3];

        // read element into array
        for (int i = 0; i < arr.length; i++) {
            // input value
            arr[i] = in .nextInt();
            year[i] = in .nextInt();

            // reverse array   
            for (int j = 0; j < arr.length / 2; j++) {
                int temp = arr[j];
                arr[j] = arr[arr.length - j - 1];
                arr[arr.length - j - 1] = temp;
            }

            for (int j = 0; j < year.length / 2; j++) {
                int temp = year[j];
                year[j] = year[year.length - j - 1];
                year[year.length - j - 1] = temp;
            }
        }

        for (int i = 0; i < arr.length; i++) {
            // print array
            System.out.println("ID :" + arr[i] + "(" + year[i] + ")");
        }
    }
}

Answer 2

You have to fill the array first then reverse it and also loop should be upto i<=arr.length-1.Reversing the array code would be

public static int[] reverseArray(int a[]) {

    int b[] = new int[a.length];
    int index = 0;
    for (int i = a.length - 1; i >= 0; i--)
    b[index++] = a[i];

    return b;
}
public static void main(String[] args) throws java.lang.Exception {
    Scanner sc = new Scanner(System. in );
    int c[] = new int[5];
    int index = 0;
    while (sc.hasNextLine()) {
        c[index++] = Integer.parseInt(sc.nextLine().trim());
    }
    System.out.println("Before Reverse " + Arrays.toString(c));
    System.out.println("After Reverse " + Arrays.toString(reverseArray(c)));
}

Input

1
2
3
4
5

Output

Before Reverse [1, 2, 3, 4, 5]
After Reverse [5, 4, 3, 2, 1]

Demo