[LeetCode] 283. Move Zeros

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.

Thought process:
Two pointers:
  1. Pointer 1 iterate through the array.
  2. Pointer 2 points to the next position of the number that's not 0.
Whenever pointer 1 reaches a number that's not 0, swap pointer 1 and 2's numbers and increment pointer 2.

Solution:
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public class Solution {
    public void moveZeroes(int[] nums) {
        int slow = 0;
        for (int fast = 0; fast < nums.length; fast++) {
            if (nums[fast] != 0) {
                int temp = nums[slow];
                nums[slow] = nums[fast];
                nums[fast] = temp;
                slow++;
            }
        }
    }
}

Time complexity: O(n).
Location: San Jose, CA, USA

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