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#include <bits/stdc++.h>

using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())

template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}

template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e;
    return o << '}';
}

#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n';
#else
#define debug(...) {}
#endif


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

    int n;
    cin >> n;
    vector<int> v(n);
    vector<vector<int>> dp(n, vector<int>(4));

    REP(i, n) {
        cin >> v[i];
        if (i == 0) {
            dp[i][0] = dp[i][3] = 1;
            continue;
        }
        dp[i][0] = min(dp[i - 1][2], dp[i - 1][3]) + 1;
        dp[i][3] = min(dp[i - 1][0], dp[i - 1][1]) + 1;
        dp[i][1] = dp[i - 1][3];
        if (v[i] < v[i - 1])
            dp[i][1] = min(dp[i][1], dp[i - 1][2]);
        dp[i][2] = dp[i - 1][0];
        if (v[i] > v[i - 1])
            dp[i][2] = min(dp[i][2], dp[i - 1][1]);
    }

    int ans = dp[n - 1][0];
    FOR(i, 1, 3)
        ans = min(ans, dp[n - 1][i]);
    cout << ans << '\n';

    return 0;
}