Separate odd and even numbers in an array

Problem :

Given an array of integers, you need to segregate odd and even numbers in an array.
Please note : Order of elements can be changed.
For example:

arr[] = {12, 17, 70, 15, 22, 65, 21, 90}
Array after separating odd and even numbers :
{12, 90, 70, 22, 15, 65, 21, 17}

• Initialise two index variable , left=0 and right=arr.length-1
• Increment left variable until you get odd number
• Decrement right variable until you get even number.
• If left < right, swap arr[left] and arr[right]
• In the end, you will see that you have even numbers on left side and odd numbers on right side.

package org.arpit.java2blog;

public class SeparateOddEvenMain {

 public static void main(String[] args) {

  int arr[]={12, 17, 70, 15, 22, 65, 21, 90};
  System.out.println("Original Array: ");
  for (int i = 0; i < arr.length; i++) {
   System.out.print(arr[i]+" ");
  }
  arr=separateEvenOddNumbers(arr);
  System.out.println("nArray after separating even and odd numbers : ");
  for (int i = 0; i < arr.length; i++) {
   System.out.print(arr[i]+" ");
  }
 }
 public static int[] separateEvenOddNumbers(int arr[])
 {
  int left=0;
  int right=arr.length-1;
  for (int i = 0; i < arr.length; i++) {

   while(arr[left]%2==0)
   {
    left++;
   }
   while(arr[right]%2==1)
   {
    right--;
   }

   if(left<right)
   {
    int temp=arr[left];
    arr[left]=arr[right];
    arr[right]=temp;
   }
  }
  return arr;
 }
}

when you run above program, you will get below output:

Original Array: 
12 17 70 15 22 65 21 90 
Array after separating even and odd numbers : 
12 90 70 22 15 65 21 17