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// orn: Ornitolog 2 | 2022-12-12 | Solution by Mikołaj Zabłocki (Dominik Korsa)
// https://sio2.mimuw.edu.pl/c/pa-2022-1/p/orn/

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

const int INFTY = 420'2137;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);

  int n;
  cin >> n;

  int incPrev = INFTY;
  int incCost = 0;
  int decPrev = -INFTY;
  int decCost = 0;
  while (n--) {
    swap(incPrev, decPrev);
    swap(incCost, decCost);
    int a;
    cin >> a;
    if (a <= incPrev) {
      ++incCost;
      incPrev = INFTY;
    } else incPrev = a;
    if (a >= decPrev) {
      ++decCost;
      decPrev = -INFTY;
    } else decPrev = a;
  }
  cout << min(incCost, decCost) << endl;

  return 0;
}