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// Marcin Knapik

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

#define FOR(i, n) for (int i = 0; i < n; i++)
#define f first
#define s second
#define pb push_back
#define all(s) s.begin(), s.end()
#define sz(s) (int)s.size()

using vi = vector<int>;

class Stan{
public:
    int MIN, mal, rosn, MAX;
};

const int INF = 1e9 + 7;
Stan dp{1, 0, 0, 1};

void solve () {
    int n;
    cin >> n;
    
    int poprz;
    cin >> poprz;

    for(int i = 2; i <= n; i++){
        int teraz;
        cin >> teraz;

        Stan next_dp {min(dp.MAX, dp.rosn) + 1, 
                      min(dp.MAX, poprz > teraz ? dp.rosn : INF),
                      min(dp.MIN, poprz < teraz ? dp.mal : INF),
                      min(dp.MIN, dp.mal) + 1
                      };

        dp = next_dp;
        poprz = teraz;
    }

    cout << min({dp.MIN, dp.MAX, dp.rosn, dp.mal}) << '\n';
}

int main () {
    ios::sync_with_stdio(0);
    cin.tie(0);

    int tests = 1;
    // cin >> tests;

    for (int test = 1; test <= tests; test++) {
        solve();
    }

    return 0;
}