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//GRT_2018
#include <bits/stdc++.h>
#define PB push_back
#define ST first
#define ND second
//mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

using namespace std;

using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;

const int nax = 50 * 1000 + 10, INF = 1e9;
int n;
int a[nax];
int dp[nax][3][3];

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	for (int i = 1; i <= n; ++i) {
		cin >> a[i];
	}
	for (int i : {0,1}) dp[1][0][i] = dp[1][1][i] = i;
	for (int i = 2; i <= n; ++i) {
		dp[i][0][0] = dp[i - 1][1][1];
		if (a[i] > a[i - 1]) dp[i][0][0] = min(dp[i][0][0], dp[i - 1][1][0]);
		dp[i][0][1] = min(dp[i-1][1][0], dp[i-1][1][1]) + 1;
		dp[i][1][0] = dp[i-1][0][1];
		if (a[i] < a[i - 1]) dp[i][1][0] = min(dp[i][1][0], dp[i-1][0][0]);
		dp[i][1][1] = min(dp[i-1][0][0], dp[i-1][0][1]) + 1;
	}
	int ans = INF;
	for (int i : {0, 1}) {
		for (int j : {0, 1}) {
			ans = min(ans, dp[n][i][j]);
		}
	}
	cout << ans;
}