Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements. https://leetcode.com/explore/challenge/card/30-day-leetcoding-challenge/528/week-1/3286/

MoveZeroesOptimal.java

import java.util.Arrays;
import java.util.stream.Collectors;

public class MoveZeroesOptimal {

  public static void main(String[] args) {
    MoveZeroesOptimal problem = new MoveZeroesOptimal();
    int[] result1 = problem.calculate(new int[] { 0, 1, 0, 3, 12 });
    System.out.println(
        "Expected: [1,3,12,0,0], " + "Result: " + Arrays.stream(result1).boxed().collect(Collectors.toList()));
  }

  /**
   * Given an array nums, write a function to move all 0's to the end of it while
   * maintaining the relative order of the non-zero elements.
   * 
   * @param nums
   * @return
   */
  public int[] calculate(final int[] nums) {

    int[] result = Arrays.copyOf(nums, nums.length);

    int countZero = 0;
    boolean moveNums = false;
    for (int i = 0; i < result.length; i++) {
      if (result[i] == 0) {
        countZero++;
        moveNums = true;
      } else if (moveNums) {
        result[i - countZero] = result[i];
        result[i] = 0;
      }
    }

    return result;
  }
}