#include <bits/stdc++.h>
#define FOR(i, n) for(int i = 0; i < (n); ++i)
#define REP(i, a, b) for(int i = (a); i < (b); ++i)
#define TRAV(i, a) for(auto &i : (a))
#define X first
#define Y second
#define MP std::make_pair
#define PR std::pair
#define SZ(x) ((int)(x).size())
typedef long long ll;
typedef std::pair<int, int> PII;
typedef std::vector<int> VI;

struct MaxTree{
	int BOTTOM;
	std::vector<PII> t;
	void build(VI A){
		BOTTOM = 1;
		while(BOTTOM < SZ(A)) BOTTOM *= 2;
		t.resize(2*BOTTOM, MP(0, -1));
		FOR(i, SZ(A)) t[i+BOTTOM] = MP(A[i], i);
		for(int i = BOTTOM-1; i >= 1; --i)
			t[i] = std::max(t[i<<1], t[(i<<1)+1]);
	}
	PII query(int a, int b){
		a += BOTTOM;
		b += BOTTOM+1;
		PII mx = MP(0, -1);
		while(a < b){
			if(a&1) mx = std::max(mx, t[a++]);
			if(b&1) mx = std::max(mx, t[--b]);
			a>>=1;
			b>>=1;
		}
		return mx;
	}
	void update(int a, int what){
		a += BOTTOM;
		t[a].X = what;
		while(a > 1){
			a >>= 1;
			t[a] = std::max(t[a<<1], t[(a<<1)+1]);
		}
	}
};
struct MinTree{
	int BOTTOM;
	std::vector<PII> t;
	void build(VI A){
		BOTTOM = 1;
		while(BOTTOM < SZ(A)) BOTTOM *= 2;
		t.resize(2*BOTTOM, MP(1000000666, -1));
		FOR(i, SZ(A)) t[i+BOTTOM] = MP(A[i], i);
		for(int i = BOTTOM-1; i >= 1; --i)
			t[i] = std::min(t[i<<1], t[(i<<1)+1]);
	}
	PII query(int a, int b){
		a += BOTTOM;
		b += BOTTOM+1;
		PII mx = MP(1000000666, -1);
		while(a < b){
			if(a&1) mx = std::min(mx, t[a++]);
			if(b&1) mx = std::min(mx, t[--b]);
			a>>=1;
			b>>=1;
		}
		return mx;
	}
	void update(int a, int what){
		a += BOTTOM;
		t[a].X = what;
		while(a > 1){
			a >>= 1;
			t[a] = std::min(t[a<<1], t[(a<<1)+1]);
		}
	}
};

bool ans[1000];
MaxTree maxtree;
MinTree mintree;

int main(){
	std::ios_base::sync_with_stdio(false);
	std::cin.tie(0);
	int n;
	std::cin >> n;
	VI A(n);
	FOR(i, n) std::cin >> A[i];
	std::map<int, VI> map;
	FOR(i, n){
		map[A[i]].push_back(i);
	}
	mintree.build(A);
	maxtree.build(A);
	TRAV(pr, map){
		if(SZ(pr.Y) >= 3) ans[111] = true;
		if(SZ(pr.Y) >= 2){
			int sc = pr.Y[1];
			if(sc < n-1){
				int big = maxtree.query(sc+1, n-1).X;
				if(big > pr.X) ans[112] = true;
				int sma = mintree.query(sc+1, n-1).X;
				if(sma < pr.X) ans[221] = true;
			}
			sc = pr.Y[SZ(pr.Y)-2];
			if(sc > 0){
				int big = maxtree.query(0, sc-1).X;
				if(big > pr.X) ans[211] = true;
				int sma = mintree.query(0, sc-1).X;
				if(sma < pr.X) ans[122] = true;
			}
			int fs = pr.Y[0];
			sc = pr.Y.back();
			if((sc-1)-(fs+1)+1 > 0){
				int big = maxtree.query(fs+1, sc-1).X;
				int sma = mintree.query(fs+1, sc-1).X;
				if(big > pr.X) ans[121] = true;
				if(sma < pr.X) ans[212] = true;
			}
		}
	}
	std::multiset<int> lef, rig;
	REP(i, 1, n) rig.insert(A[i]);
	lef.insert(A[0]);
	REP(i, 1, n-1){
		rig.erase(rig.find(A[i]));
		auto lbb = std::prev(lef.end());
		auto lbs = lef.upper_bound(A[i]);
		auto rbb = std::prev(rig.end());
		auto rbs = rig.upper_bound(A[i]);
		if(*lbb > A[i] && rbs != rig.end() && *lbb > *rbs) ans[312] = true;
		if(*rbb > A[i] && lbs != lef.end() && *rbb > *lbs) ans[213] = true;
		auto lss = lef.begin();
		auto lsb = lef.lower_bound(A[i]);
		if(lsb == lef.begin()) lsb = lef.end();
		else lsb--;
		auto rss = rig.begin();
		auto rsb = rig.lower_bound(A[i]);
		if(rsb == rig.begin()) rsb = rig.end();
		else rsb--;
		if(*lss < A[i] && rsb != rig.end() && *lss < *rsb) ans[132] = true;
		if(*rss < A[i] && lsb != lef.end() && *rss < *lsb) ans[231] = true;
		if(*lbb > A[i] && *rss < A[i]) ans[321] = true;
		if(*rbb > A[i] && *lss < A[i]) ans[123] = true;

		lef.insert(A[i]);
	}
	FOR(i, 1000){
		if(ans[i]){
			std::cout << i << "\n";
		}
	}

	return 0;
}