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

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n;
    vector<int> sounds, s2;
    cin >> n;
    for (int a, i = 0; i < n; i++) {
        cin >> a;
        sounds.push_back(a);
    }
s2=sounds;
    int result[] = {0, 0};
    int inf = (int)1e9 + 9;
    int type = 1;

    for (int i = 0; i < n; i++) {
        int prev = (i == 0 ? inf : sounds[i - 1]);
        int next = (i == n - 1 ? type * inf : sounds[i + 1]);
        type *= -1;
        if (prev <= sounds[i] || sounds[i] >= next) {
            result[0]++;
            sounds[i] = (-type) * inf;
        }
    }
    sounds=s2;

    type = -1;
    for (int i = 0; i < n; i++) {
        int prev = (i == 0 ? -inf : sounds[i - 1]);
        int next = (i == n - 1 ? type * inf : sounds[i + 1]);
        type *= -1;
        if (prev >= sounds[i] || sounds[i] <= next) {
            result[1]++;
            sounds[i] = (-type) * inf;
        }
    }

    cout << max(result[0], result[1]);
    return 0;
}