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#include<bits/stdc++.h>
#define FOR(i,a,b) for(int i=a;i<(int)b;++i)
#define FORD(i,a,b) for(int i=a;i>=(int)b;--i)
#define PB push_back
#define EB emplace_back
#define FI first
#define SE second
#define umap unordered_map
#define uset unordered_set
#define vi vector<int>
#define vvi vector<vi>
#define vll vector<ll>
#define vvll vector<vll>
#define vpii vector<pii>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ALL(X) (X).begin(),(X).end()
#ifndef DEBUG
#define endl (char)10
#endif
using namespace std;
using ll = long long;
using ld = long double;

template <class T>
istream& operator>> (istream& is, vector<T>& vec){
    FOR(i,0,vec.size()) is >> vec[i];
    return is;
}
template <class T>
ostream& operator<< (ostream& os, vector<T>& vec){
    for(auto& t : vec) os << t << " ";
    return os;
}
template<class T, class U>
ostream& operator<< (ostream& os, const pair<T, U>& p){
    os << p.FI << " " << p.SE;
    return os;
}
template<class T, class U>
istream& operator>> (istream& is, pair<T, U>& p){
    is >> p.FI >> p.SE;
    return is;
}

int napraw(vi& V, int zn, int zj){
    int ans = zj;
    int prev = (zj ? (zn < 0 ? INT_MAX : INT_MIN) : V[0]);
    FOR(i,1,V.size()){
        if (zn > 0){
            if (prev >= V[i]){
                prev = INT_MAX;
                ans++;
            } else prev = V[i];
        } else {
            if (prev <= V[i]){
                prev = INT_MIN;
                ans++;
            } else prev = V[i];
        }
         zn *= -1;
    }
    return ans;
}

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vi V(n);
    cin >> V;
    cout << min({
        napraw(V, 1, 0),
        napraw(V, -1, 0),
        napraw(V, 1, 1),
        napraw(V, -1, 1)
    }) << endl;
}