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#include <bits/stdc++.h>

using namespace std;

constexpr int INF = 1000000000;
constexpr int MINF = - INF;

int f(vector<int> const& a, bool bigger, int previ) {
    int r = 0;

    for (int i : a) {
        if (bigger) {
            if (previ >= i) {
                ++r;
                previ = INF;
            } else {
                previ = i;
            }
        } else {
            if (previ <= i){
                ++r;
                previ = MINF;
            } else {
                previ = i;
            }
        }

        bigger = not bigger;
    }

    return r;
}

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

    vector<int> a(n);
    for (int &i : a)
        cin >> i;

    return min(f(a, true, MINF), f(a, false, INF));
}

int main() {
    ios_base::sync_with_stdio(false), cin.tie(nullptr);
    cout << solve() << '\n';
    return 0;
}