class Solution {
    public void moveZeroes(int[] nums) {
        //Do not return anything, modify nums in-place instead.
        int l = 0;
        for(int r = 0; r < nums.length; r++)
            if(nums[r] != 0) {
                int tmp = nums[l];
                nums[l] = nums[r];
                nums[r] = tmp;
                l += 1;
            }
    }
}