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#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define vi vector<int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10), cin.tie(0), cout.tie(0);
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define all(c) (c).begin(), (c).end()
#define sz(X) (int)((X).size())
typedef long double ld;
typedef unsigned long long ull;
typedef long long ll;
#ifdef LOCAL
ostream &operator<<(ostream &out, string str) {
   for (char c : str)
      out << c;
   return out;
}
template <class L, class R> ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.st << ", " << p.nd << ")"; }
template <class L, class R, class S> ostream &operator<<(ostream &out, tuple<L, R, S> p) {
   auto &[a, b, c] = p;
   return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
   out << '{';
   for (auto it = a.begin(); it != a.end(); it = next(it))
      out << (it != a.begin() ? ", " : "") << *it;
   return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts> void dump(T a, Ts... x) {
   cerr << a << ", ";
   dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...)
#endif

const int MAXN = 1e5 + 99;
int dp[MAXN][2];

int solve(vector<int> X) {
   int n = sz(X);
   dp[0][0] = 0;
   dp[0][1] = 1;

   auto f = [&](int a, int b, bool incr) { return incr ? a < b : a > b; };

   for (int i = 1; i < n; i++) {
      dp[i][1] = min(dp[i - 1][0], dp[i - 1][1]) + 1;
      dp[i][0] = f(X[i - 1], X[i], i & 1) ? min(dp[i - 1][0], dp[i - 1][1]) : dp[i - 1][1];
      debug(i, dp[i][0], dp[i][1]);
   }
   return min(dp[n - 1][0], dp[n - 1][1]);
}

int32_t main() {
   _upgrade;
   int n;
   cin >> n;
   vector<int> X(n);
   for (auto &x : X)
      cin >> x;

   auto A = solve(X);
   for (auto &x : X)
      x = -x;
   auto B = solve(X);
   debug(A, B);
   cout << min(A, B) << endl;
}