1 #include<iostream>
 2 using namespace std;
 3 int CompactIntegers(int *arr,int n)
 4 {
 5     //直接从头到尾遍历整个数组，是0就将n减1，同时数组下表往前移
 6     for (int i = 0; i < n; i++)
 7     {
 8         if (arr[i] == 0)
 9         {
10             //将所有元素向前移
11             int j = i;
12             for (; j < n - 1; j++)
13             {
14                 arr[j] = arr[j + 1];
15             }
16             //将要判断的元素的下标前移
17             i = i - 1;
18             //非0元素个数减1
19             n--;
20         }
21     }
22     return n;
23 }
24 
25 int main(void)
26 {
27     int n;
28     cin >> n;
29     int* arr = new int[n];
30     for (int i = 0; i < n; i++)
31     {
32         cin >> arr[i];
33     }
34     int t = CompactIntegers(arr, n);
35     cout << t << endl;
36     if (t == 0)
37     {
38         return 0;
39     }
40     else
41     {
42         for (int i = 0; i < t - 1; i++)
43         {
44             cout << arr[i] << " ";
45         }
46         cout << arr[t - 1];
47     }
48     return 0;
49 }