Tanya and Stairways

Description:

Input:

The first line contains $$$n$$$ ($$$1 \le n \le 1000$$$) — the total number of numbers pronounced by Tanya.

The second line contains integers $$$a_1, a_2, \dots, a_n$$$ ($$$1 \le a_i \le 1000$$$) — all the numbers Tanya pronounced while climbing the stairs, in order from the first to the last pronounced number. Passing a stairway with $$$x$$$ steps, she will pronounce the numbers $$$1, 2, \dots, x$$$ in that order.

The given sequence will be a valid sequence that Tanya could have pronounced when climbing one or more stairways.

Output:

In the first line, output $$$t$$$ — the number of stairways that Tanya climbed. In the second line, output $$$t$$$ numbers — the number of steps in each stairway she climbed. Write the numbers in the correct order of passage of the stairways.

Sample Input:

7
1 2 3 1 2 3 4

Sample Output:

2
3 4 

Sample Input:

4
1 1 1 1

Sample Output:

4
1 1 1 1 

Sample Input:

5
1 2 3 4 5

Sample Output:

1
5 

Sample Input:

5
1 2 1 2 1

Sample Output:

3
2 2 1