Move Zeroes

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.

For example, given nums = [0, 1, 0, 3, 12], after calling your function, nums should be [1, 3, 12, 0, 0].

Note:

  1. You must do this in-place without making a copy of the array.
  2. Minimize the total number of operations.

Solution:

  1. public class Solution {
  2.   public void moveZeroes(int[] nums) {
  3.     int i = 0, j = 0;
  5.     while (j < nums.length) {
  6.       if (nums[j] != 0) {
  7.         swap(nums, i++, j);
  8.       }
  9.       j++;
  10.     }
  11.   }
  13.   void swap(int[] nums, int i, int j) {
  14.     int tmp = nums[i];
  15.     nums[i] = nums[j];
  16.     nums[j] = tmp;
  17.   }
  18. }