from bisect import bisect_left
def solve(n,a):
  ans=0
  dp_back=[10**20]*n
  b=[]
  for i in a[::-1]:
    dp_back[bisect_left(dp_back,i)]=i
    b.append(bisect_left(dp_back,10**20))
  b=b[::-1]
  dp=[10**20]*n
  for i in range(n):
    dp[bisect_left(dp,a[i])]=a[i]
    ans=max(ans,min(b[i],bisect_left(dp,10**20)))
  return ans
n=int(input())
a=list(map(int,input().split()))
ans=solve(n,a)
for i in range(n):a[i]*=-1
ans=max(ans,solve(n,a))
print(ans-1)