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.

这道题一开始没看清，以为直接换到最后就行了，后来发现要换好之后还是原来的顺序，这才是难点。还好解决方法也不难

public class Solution {
    public void moveZeroes(int[] nums) {
        int pos = 0;
        for(int i=0;i<nums.length;i++){
            if(nums[i] != 0){
                nums[pos] = nums[i];
                pos++;
            }
        }
        for(int i=pos;i<nums.length;i++){
            nums[i] =0;
        }
    }
}