#include<bits/stdc++.h>
using namespace std;

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	vector<int>a(n);
	for (int i = 0; i < n; i++)
		cin >> a[i];
	int ans = 0;
	while (a.size() > 1)
	{
		int maxx = 0;
		int m = a.size();
		for (int i = 0; i < m; i++)
		{
			if (i == 0)
				maxx = max(maxx, a[i + 1]);
			else if (i == m - 1)
				maxx = max(maxx, a[i - 1]);
			else
				maxx = max(maxx, min(a[i - 1], a[i + 1]));
		}
		vector<int>b;
		for (int i = 0; i < m; i++)
			if (a[i] > maxx)b.push_back(a[i]);
		a = b;
		ans++;
	}
	cout << ans;
	return 0;
}