"""

https://yukicoder.me/problems/no/1804

辞書順最大・最小のLISを見付ける

"""

import sys
from sys import stdin

#return lexicography minimum LIS
def LISMIN(lis):
    import bisect

    dic = {}
    
    seq = []
    for c in lis:
        ind = bisect.bisect_left(seq,c)
        if ind == len(seq):
            seq.append(c)
            if len(seq) == 1:
                dic[c] = None
            else:
                dic[c] = seq[-2]
        else:
            seq[ind] = c
            if ind == 0:
                dic[c] = None
            else:
                dic[c] = seq[ind-1]

    #print (seq)
    ret = []
    v = seq[-1]
    while v != None:
        ret.append(v)
        v = dic[v]
    ret.reverse()

    return ret
    

N = int(stdin.readline())
P = list(map(int,stdin.readline().split()))

LM = LISMIN(P)

P.reverse()
for i in range(N):
    P[i] *= -1
RM = LISMIN(P)
RM.reverse()
for i in range(len(RM)):
    RM[i] *= -1

ans = []
for i in range(len(LM)):
    if LM[i] == RM[i]:
        ans.append(LM[i])
print (len(ans))
print (*ans)