//  (>_<)ムリ!!

#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
using namespace std;

struct node{
	int cnt;
	int l;
	int m;
	node():cnt(0),l(0),m(0){}
	bool operator < (const node& x) const{
		return cnt < x.cnt;
	}
	bool operator == (const node& x) const{
		return (cnt == x.cnt) && (l == x.l) && (m == x.m);
	}
};

struct val{
	node a;
	node b;
	val operator +(const val& x){
		val ret;
		priority_queue<node, vector<node>, less<node>> pq;
		pq.push(a);
		pq.push(b);
		pq.push(x.a);
		pq.push(x.b);
		ret.a = pq.top();
		pq.pop();
		bool ok = false;
		while(pq.size() && !ok){
			if(pq.top().l != ret.a.l){
				ok = true;
				ret.b = pq.top();
			}else{
				pq.pop();
			}
		}
		return ret;
	}
};

ostream& operator << (ostream& os, const node& x){
	os << "{" << x.cnt << ", " << x.l << ", " << x.m << "} ";
	return os;
}


ostream& operator << (ostream& os, const val& x){
	os << "{ " << x.a << ", " << x.b << "} ";
	return os;
}

val comp(const val& x, const val& y){
	val ret;
	
	if(x.a < y.a){
		ret.a = y.a;

		if(x.a < y.b){
			if(ret.a.m != y.b.m) ret.b = y.b;
			else ret.b = x.a;
		}else{
			if(ret.a.m != x.a.m) ret.b = x.a;
			else ret.b = y.b;
		}
	}else{
		ret.a = x.a;
		if(x.b < y.a){
			if(ret.a.m != y.a.m) ret.b = y.a;
			else ret.b = x.b;
		}else{
			if(ret.a.m != x.b.m) ret.b = x.b;
			else ret.b = y.a;
		}
	}

	return ret;
}

val hoge(const val& x, int a){
	val ret;
	if(x.a.l != a){
		ret.a = x.a;
		if(x.b.l != a){
			ret.b = x.b;
		}
	}else if(x.b.l != a){
		ret.a = x.b;
	}
	return ret;
}

class seg{
public:
	vector<val> v;
	int size;
	seg(int n){
		size = 1;
		while(size<n){
			size <<= 1;
		}
		v.resize(2*size);
	}

	void update(int l, int r, val& x, int lb, int ub, int pos){
		if(ub<=l || r<=lb) return;
		if(l<=lb && ub<=r){
			v[pos] = v[pos]+x;
			return;
		}
		update(l,r,x, lb,(lb+ub)/2, pos*2+1);
		update(l,r,x, (lb+ub)/2,ub, pos*2+2);
		v[pos] = v[pos*2+1] + v[pos*2+2];
	}
	void update(int l, int r, val& x){
		update(l,r,x,0,size,0);
	}

	val get(int l, int r, int a, int cnt, int lb, int ub, int pos){
		if(ub<=l || r<=lb) return val();
		if(l<=lb && ub<=r){
			val ret;
			if(cnt == 2){
				ret = hoge(v[pos], a);
				if((ub-lb>1)){
					ret = comp(get(l,r,a,1, lb,(lb+ub)/2, pos*2+1) , get(l,r,a,1, (lb+ub)/2,ub, pos*2+2));
					//ret = comp(ret, tmp);
				}
			}else{
				ret = hoge(v[pos], a);
			}

			return ret;
		}
		val x;
		x = get(l,r, a,cnt, lb, (lb+ub)/2, pos*2+1);
		//x = hoge(x, a);

		val y;
		y = get(l,r, a,cnt, (lb+ub)/2, ub, pos*2+2);
		//y = hoge(y, a);

		val ret = comp(x,y);
		return ret;
	}

	val get(int l, int r, int a){
		return get(l,r, a,2, 0,size,0);
	}
};

template<class T>
vector<T> compress(vector<T> a, int& size){
	auto b = a;
	sort(b.begin(), b.end());
	b.erase( unique(b.begin(), b.end()), b.end());
	for(int i=0; i<a.size(); i++){
		a[i] = lower_bound(b.begin(), b.end(), a[i]) - b.begin() +1;
	}
	size = b.size();
	return a;
}

val func(const val& x, int a, int i){
	//cerr << x << " ";
	val ret;
	if(x.a.cnt == 0){
		ret.a.m = a;
		ret.a.cnt = 1;
		ret.a.l = 1e6;
		return ret;
	}else{
		ret.a.m = a;
		ret.a.cnt = x.a.cnt+1;
		ret.a.l = x.a.m;

		ret.b.m = a;
		ret.b.cnt = x.b.cnt+1;
		ret.b.l = x.b.m;
		if(ret.b.l == 0) ret.b.l = 1e6;
	}
	if(ret.a == ret.b){
		if(ret.a.cnt == 1){
			ret.b = node();
		}else{
			ret.b.cnt = 1;
			ret.b.l = 1e6;
		}
	}
}

int main(){
	int n;
	cin >> n;
	vector<int> a(n);
	for(int i=0; i<n; i++){
		scanf("%d", &a[i]);
	}
	int m;
	a = compress(a, m);

	a.erase( unique(a.begin(), a.end()), a.end());
	n = a.size();

	seg inc(m+1);
	seg dec(m+1);

	for(int i=0; i<n; i++){
		val s = func(inc.get(a[i]+1, m+1, a[i]), a[i], i);
		//cerr << s << endl;

		val t = func(dec.get(0, a[i], a[i]), a[i], i);
		//cerr << t << endl;

		dec.update(a[i],a[i]+1, s);
		inc.update(a[i],a[i]+1, t);
	}

	int ans = 0;
	val x = inc.get(0,m+1, 1e9);
	val y = dec.get(0,m+1, 1e9);
	ans = max({x.a.cnt, x.b.cnt, y.a.cnt, y.b.cnt});
	if(ans <= 2) ans = 0;
	cout << ans << endl;


	return 0;
}