package me.ramswaroop.arrays;
import java.util.Arrays;
/**
* Created by IntelliJ IDEA.
*
* @author: ramswaroop
* @date: 7/27/15
* @time: 8:40 PM
*/
public class ReverseArray {
/**
* Iterative method to reverse the entire array.
*
* @param a
*/
public static void reverse(int[] a) {
int temp;
for (int i = 0, j = a.length - 1; i < j; i++, j--) {
// swap elements
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
/**
* Recursive method to reverse the array elements from
* {@param i} index to {@param j} index (both inclusive).
*
* @param a
* @param i
* @param j
*/
public static void reverseRecursive(int[] a, int i, int j) {
if (i > j) return;
int temp = a[i];
a[i] = a[j];
a[j] = temp;
reverseRecursive(a, ++i, --j);
}
public static void main(String a[]) {
int[] ar = new int[]{1, 2, 3, 4, 5};
System.out.println(Arrays.toString(ar));
reverse(ar);
System.out.println(Arrays.toString(ar));
reverseRecursive(ar, 0, ar.length - 1);
System.out.println(Arrays.toString(ar));
}
}