Little girl Tanya climbs the stairs inside a multi-storey building. Every time Tanya climbs a stairway, she starts counting steps from $1$ to the number of steps in this stairway. She speaks every number aloud. For example, if she climbs two stairways, the first of which contains $3$ steps, and the second contains $4$ steps, she will pronounce the numbers $1, 2, 3, 1, 2, 3, 4$.

You are given all the numbers pronounced by Tanya. How many stairways did she climb? Also, output the number of steps in each stairway.

The given sequence will be a valid sequence that Tanya could have pronounced when climbing one or more stairways.
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.
7
1 2 3 1 2 3 4
2
3 4 
4
1 1 1 1
4
1 1 1 1 
5
1 2 3 4 5
1
5 
5
1 2 1 2 1
3
2 2 1 
1
1
1
1 
48
1 2 3 4 1 2 3 1 1 2 3 1 2 3 4 1 1 2 3 4 1 2 3 4 1 2 3 4 1 1 2 1 2 1 2 1 1 2 1 2 1 2 3 1 2 1 2 1
20
4 3 1 3 4 1 4 4 4 1 2 2 2 1 2 2 3 2 2 1 
2
1 2
1
2 
3
1 1 2
2
1 2 
4
1 1 2 3
2
1 3 
8
1 2 3 1 2 3 4 5
2
3 5 
5
1 1 1 2 3
3
1 1 3 
from math import inf
from collections import *
import math, os, sys, heapq, bisect, random, threading
from functools import lru_cache, reduce
from itertools import *
import sys


def inp(): return sys.stdin.readline().rstrip("\r\n")


def out(var): sys.stdout.write(str(var))  # for fast output, always take string


def inpu(): return int(inp())


def lis(): return list(map(int, inp().split()))


def stringlis(): return list(map(str, inp().split()))


def sep(): return map(int, inp().split())


def strsep(): return map(str, inp().split())


def fsep(): return map(float, inp().split())


M, M1 = 1000000007, 998244353


def main():
    #sys.stdin = open("test", 'r')
    t = inpu()
    a = lis()

    res = 0
    reslis = []
    count = 0
    for i in a:
        count += 1
        if i == 1:
            reslis.append(count)
            res += 1
            count = 0
    reslis.append(count + 1)

    print(res)
    print(*reslis[1:])



if __name__ == '__main__':
    # sys.setrecursionlimit(1000000)
    # threading.stack_size(1024000)
    # threading.Thread(target=main).start()
    main()

		 	   	 		  	 		  				 		 		