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#include<cstdio>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<string>
#include<vector>
#include<cmath>
#include<set>
#include<stack>

using namespace std;

typedef vector<int> VI;
typedef long long LL;
typedef vector<LL> VLL;
typedef pair<int, int> PII;

#define FOR(x, b, e) for(int x=b; x<=(e); ++x)
#define FORD(x, b, e) for(int x=b; x>=(e); --x)
#define REP(x, n) for(int x=0; x<(n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FOREACH(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define PB push_back
#define ST first
#define ND second

int sign(int x) {
    if (x > 0) return 1;
    if (x < 0) return -1;
    return 0;
}

int count(VI &rec, int direction) {
    int result = 0;
    REP(i, rec.size() - 1) {
        if (sign(rec[i + 1] - rec[i]) != direction) {
            result++;
            i++;
        } else direction *= -1;
    }
    return result;
}

int main() {
	ios_base::sync_with_stdio(0);
    cin.tie(NULL); cout.tie(NULL);
    int n;
    cin >> n;
    VI recording(n);
    REP(i, n) cin >> recording[i];
    cout << min(count(recording, 1), count(recording, -1)) << '\n';
    return 0;
}