using System;
using System.Linq;
using System.Diagnostics;
using System.Collections.Generic;
using Debug = System.Diagnostics.Debug;
using StringBuilder = System.Text.StringBuilder;
using System.Numerics;

namespace Program
{

    public class Solver
    {
        /// <summary>
        /// O(NlogN)
        /// </summary>
        public void Solve()
        {
            //dp[prev,now]=lenをセグメント木でやる
            var n = int.Parse(Console.ReadLine());
            var a = Console.ReadLine().Split().Select(int.Parse).ToArray();
            var S = a.Distinct().ToList();
            S.Add(-1); S.Add(int.MaxValue);//番兵
            S.Sort();
            for (int i = 0; i < n; i++)
                a[i] = S.BinarySearch(a[i]);//座圧
            var sz = S.Count;
            var inc = new SegTree.SegmentTree(sz);//右端の２つの竹について単調増加な最長門松部分列
            var dec = new SegTree.SegmentTree(sz);//右端の2つの竹について単調減少な最長門松部分列
            inc.Update(sz - 1, 0, 0);
            dec.Update(0, 0, sz - 1);
            foreach (var i in a)
            {
                //下がる
                {
                    var max = inc.Query(i + 1, sz, i);//prevがi以外であってnowがiより大きいもの
                    var pos = max.J;
                    var sec = Triplet.Max(inc.Query(i + 1, pos, i), inc.Query(pos + 1, sz, i));//pos以外から来て，prevがi以外であってnowがiより大きいもの
                    dec.Update(i, max.I + 1, max.J);//dp[pos1,i]=dp[prev1,pos1]+1
                    dec.Update(i, sec.I + 1, sec.J);//dp[pos2,i]=dp[prev2,pos2]+1
                }
                //上がる
                {
                    var max = dec.Query(0, i, i);//prevがi以外であってnowがiより小さいもの
                    var pos = max.J;
                    var sec = Triplet.Max(dec.Query(0, pos, i), dec.Query(pos + 1, i, i));//pos以外から来て，prevがi以外であってnowがiより大きいもの
                    inc.Update(i, max.I + 1, max.J);//dp[pos1,i]=dp[prev1,pos1]+1
                    inc.Update(i, sec.I + 1, sec.J);//dp[pos2,i]=dp[prev2,pos2]+1
                }
            }
            var ans = Math.Max(inc.Query(0, sz, -1).I, dec.Query(0, sz, -1).I);
            if (ans < 3) ans = 0;
            Console.WriteLine(ans);
        }

        static T[] Enumerate<T>(int n, Func<int, T> f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(i); return a; }
        static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }
    }
}

#region main
static class Ex
{
    static public void Main()
    {
        var solver = new Program.Solver();
        solver.Solve();
    }
}
#endregion

namespace SegTree
{
    using K = Triplet<int, int, int>;
    #region SegTree
    [System.Diagnostics.DebuggerDisplay("Data={ToString()}")]
    public class SegmentTree
    {
        static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }
        readonly K min = new K(-1000000000, -1, -1);
        readonly Pair<K, K> MIN;
        int n;
        Pair<K, K>[] data;//length,now,prevのtripletのペア，
        public SegmentTree(int size)
        {
            MIN = new Pair<K, K>(min, min);
            n = 1;
            while (n < size)
                n <<= 1;
            data = new Pair<K, K>[n << 1];
            for (int i = 0; i < n << 1; i++)
                data[i] = MIN;

        }
        /// <summary>
        /// 葉ノードについて，fromが一致しないようにlengthを最大化
        /// </summary>
        void update(ref Pair<K, K> data, K t)
        {
            if (data.x.I < t.I)
            {
                if (data.x.K == t.K)
                    data.x = t;
                else { data.y = data.x; data.x = t; }
            }
            else if (data.y.I < t.I)
            {
                if (data.x.K != t.K)
                    data.y = t;
            }
        }
        /// <summary>
        /// k番目の葉ノードにfromからきたときに長さv
        /// </summary>
        public void Update(int k, int v, int from)
        {
            var t = new K(v, k, from);
            k += n;
            update(ref data[k], t);
            k >>= 1;
            while (k > 0)
            {
                update(ref data[k], t);
                k >>= 1;
            }

        }
        /// <summary>
        /// [a,b)のfromがnowでないようなlengthの最大値を求める．
        /// </summary>
        public K Query(int a, int b, int now) { return Query(a, b, now, 1, 0, n); }
        private K Query(int a, int b, int now, int k, int l, int r)
        {
            if (r <= a || b <= l)
                return min;
            if (a <= l && r <= b)
            {
                if (data[k].x.K != now)
                    return data[k].x;
                else return data[k].y;
            }
            else
            {
                var vl = Query(a, b, now, k << 1, l, (l + r) >> 1);
                var vr = Query(a, b, now, (k << 1) + 1, (l + r) >> 1, r);
                return Triplet.Max(vl, vr);
            }
        }

    }
    #endregion
}
#region Triplet<ST,FT,TT>
static public class Triplet
{
    static public Triplet<FT, ST, TT> Create<FT, ST, TT>(FT f, ST s, TT t)
        where FT : IComparable<FT>
        where ST : IComparable<ST>
        where TT : IComparable<TT>
    { return new Triplet<FT, ST, TT>(f, s, t); }
    static public Triplet<FT, ST, TT> Min<FT, ST, TT>(Triplet<FT, ST, TT> p, Triplet<FT, ST, TT> q)
        where FT : IComparable<FT>
        where ST : IComparable<ST>
        where TT : IComparable<TT>
    { return (p.CompareTo(q) <= 0) ? p : q; }
    static public Triplet<FT, ST, TT> Max<FT, ST, TT>(Triplet<FT, ST, TT> p, Triplet<FT, ST, TT> q)
        where FT : IComparable<FT>
        where ST : IComparable<ST>
        where TT : IComparable<TT>
    { return (p.CompareTo(q) >= 0) ? p : q; }
}
public struct Triplet<FT, ST, TT> : IComparable<Triplet<FT, ST, TT>>
    where FT : IComparable<FT>
    where ST : IComparable<ST>
    where TT : IComparable<TT>
{
    public FT I;
    public ST J;
    public TT K;
    public Triplet(FT i, ST j, TT k) : this() { I = i; J = j; K = k; }
    public int CompareTo(Triplet<FT, ST, TT> other)
    {
        var cmp = I.CompareTo(other.I);
        if (cmp != 0) return cmp;
        cmp = J.CompareTo(other.J);
        if (cmp != 0) return cmp;
        return K.CompareTo(other.K);
    }
    public override string ToString() { return string.Format("{0} {1} {2}", I, J, K); }
}
#endregion
#region Compair
static public class Pair
{
    static public Pair<FT, ST> Create<FT, ST>(FT f, ST s)
        where FT : IComparable<FT>
        where ST : IComparable<ST>
    { return new Pair<FT, ST>(f, s); }
    static public Pair<FT, ST> Min<FT, ST>(Pair<FT, ST> p, Pair<FT, ST> q)
        where FT : IComparable<FT>
        where ST : IComparable<ST>
    { return (p.CompareTo(q) <= 0) ? p : q; }
    static public Pair<FT, ST> Max<FT, ST>(Pair<FT, ST> p, Pair<FT, ST> q)
        where FT : IComparable<FT>
        where ST : IComparable<ST>
    { return (p.CompareTo(q) >= 0) ? p : q; }
}
public struct Pair<FT, ST> : IComparable<Pair<FT, ST>>
    where FT : IComparable<FT>
    where ST : IComparable<ST>
{
    public FT x;
    public ST y;
    public Pair(FT f, ST s) : this() { x = f; y = s; }

    public int CompareTo(Pair<FT, ST> other)
    {
        var cmp = x.CompareTo(other.x);
        return cmp != 0 ? cmp : y.CompareTo(other.y);
    }
    public override string ToString() { return string.Format("{0} {1}", x, y); }
}
#endregion