use std::cmp::*;

fn solve(a: &Vec<i64>) -> Vec<usize> {
    let n = a.len();
    let mut dp = vec![std::i64::MAX; n];
    let mut from_right_pos = vec![0; n];
    for i in 0..n {
        let pointer = dp.lower_bound(&a[i]);
        dp[pointer] = a[i];
        from_right_pos[i] = dp.lower_bound(&std::i64::MAX);
    }
    from_right_pos
}

fn main() {
    let n = read::<usize>();
    let mut a = read_vec::<i64>();

    let mut ans = 0;
    for _ in 0..2 {
        let temp1 = solve(&a);
        a.reverse();
        let mut temp2 = solve(&a);
        temp2.reverse();
        a.reverse();
        for i in 0..n {
            ans = max(ans, min(temp1[i], temp2[i]) - 1);
        }
        a = a.iter().map(|&x| -x).collect::<Vec<_>>();
    }

    println!("{}", ans);
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}

pub trait BinarySearch<T> {
    fn lower_bound(&self, x: &T) -> usize;
}

impl<T: Ord> BinarySearch<T> for [T] {
    fn lower_bound(&self, x: &T) -> usize {
        let mut low = 0;
        let mut high = self.len();

        while low != high {
            let mid = (low + high) / 2;
            match self[mid].cmp(x) {
                Ordering::Less => {
                    low = mid + 1;
                }
                Ordering::Equal | Ordering::Greater => {
                    high = mid;
                }
            }
        }
        low
    }
}