#include "bits/stdc++.h"
//#include "atcoder/all"
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int N;
	cin >> N;
	vector<int>A(N);
	rep(i, N) { cin >> A[i]; }
	//ソート済みなら0回
	{
		bool b = true;
		rep(i, N - 1) {
			if (A[i] > A[i + 1]) {
				b = false;
			}
		}
		if (b) {
			cout << 0 << endl;
			return 0;
		}
	}
	//1個で出来るかの判定
	{
		vector<int>count(N);
		rep(i, N) {
			if (0 == i) {
				count[i] = 0;
				continue;
			}
			count[i] = count[i - 1];
			if (A[i - 1] > A[i]) {
				count[i]++;
			}
		}
		vector<int>maxA(N);
		rep(i, N) {
			if (0 == i) {
				maxA[i] = A[i];
				continue;
			}
			maxA[i] = max(maxA[i - 1], A[i]);
		}
		vector<int>minA(N + 1, INF + 1);
		rrep(i, N) {
			minA[i] = min(minA[i + 1], A[i]);
		}
		rep(i, N) {
			if ((1 == count[i]) && (A[i] <= A[0]) && (maxA[i] <= minA[i + 1]) && (count[N - 1]) == 1) {
				cout << 1 << endl;
				return 0;
			}
		}
	}
	//2個あればどうにでもなる。(バブルソートが出来るので)
	cout << 2 << endl;
	return 0;
}