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#include <iostream>
#include <vector>
#include <chrono>
#include <random>
#include <cassert>

std::mt19937 rng((int) std::chrono::steady_clock::now().time_since_epoch().count());

int main() {
    std::ios_base::sync_with_stdio(false); std::cin.tie(NULL);
    int n;
    std::cin >> n;
    const int INF = (int)1e9 + 1;
    int last = -INF;
    int ans = 0;
    for(int i = 0; i < n; i++) {
        int x;
        std::cin >> x;
        if(i % 2 == 0) {
            if(x > last) {
                last = x;
            } else {
                last = INF;
                ans++;
            }
        } else {
            if(x < last) {
                last = x;
            } else {
                last = -INF;
                ans++;
            }
        }
    }
    std::cout << ans << '\n';
}