Partition Array by Odd and Even

Partition an integers array into odd number first and even number second.

Example
Given [1, 2, 3, 4], return [1, 3, 2, 4]

Challenge
Do it in-place.

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双指针

public class Solution {
    /**
     * @param nums: an array of integers
     * @return: nothing
     */
    public void partitionArray(int[] arr) {
        /* Initialize left and right indexes */
        int left = 0, right = arr.length - 1;
        while (left < right)
        {
            /* Increment left index while we see 0 at left */
            while (arr[left]%2 == 0 && left < right)
                left++;

            /* Decrement right index while we see 1 at right */
            while (arr[right]%2 == 1 && left < right)
                right--;

            if (left < right)
            {
                /* Swap arr[left] and arr[right]*/
                int temp = arr[left];
                arr[left] = arr[right];
                arr[right] = temp;
                left++;
                right--;
            }
        }
    }
}