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#include <bits/stdc++.h>

using namespace std;

int n, wynik;
int t[100000];
int dp[100000][4];

int main() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> t[i];
    }
    dp[1][1] = 1;
    dp[1][3] = 1;
    for (int i = 2; i <= n; i++) {
        dp[i][0] = dp[i - 1][3]; 
        dp[i][1] = min(dp[i - 1][2], dp[i - 1][3]) + 1;
        dp[i][2] = dp[i - 1][1];
        dp[i][3] = min(dp[i - 1][0], dp[i - 1][1]) + 1;
        if (t[i] > t[i - 1]) dp[i][2] = min(dp[i][2], dp[i - 1][0]);
        if (t[i] < t[i - 1]) dp[i][0] = min(dp[i][0], dp[i - 1][2]);
    }
    wynik = min(min(dp[n][0], dp[n][1]), min(dp[n][2], dp[n][3]));
    cout << wynik << endl;
}