import sys; input = sys.stdin.buffer.readline
sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")
import bisect

def getlist():
	return list(map(int, input().split()))

def LIS(N, A):
	DP = [INF] * N
	L = [None] * N

	for i in range(N):
		x = bisect.bisect_left(DP, A[i])
		DP[x] = A[i]
		L[i] = bisect.bisect_left(DP, INF)

	return L

def LISrev(N, A):
	DP = [INF] * N
	L = [None] * N

	for i in range(N):
		x = bisect.bisect_left(DP, -A[i])
		DP[x] = -A[i]
		L[i] = bisect.bisect_left(DP, INF)

	return L

#処理内容
def main():
	N = int(input())
	A = getlist()
	leftup = LIS(N, A)
	rightup = LIS(N, A[::-1])
	rightup = rightup[::-1]
	# print(leftup)
	# print(rightup)
	leftdown = LISrev(N, A)
	rightdown = LISrev(N, A[::-1])
	rightdown = rightdown[::-1]
	# print(leftdown)
	# print(rightdown)

	ans = 0
	for i in range(N):
		ans = max(ans, min(leftup[i], rightup[i]) - 1)
		ans = max(ans, min(leftdown[i], rightdown[i]) - 1)

	print(ans)

if __name__ == '__main__':
	main()