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#include <iostream>
#include <algorithm>
#include <cstdio>
#include <math.h>
#include <iomanip>
#include <set>
#include <list>
#include <queue>
#include <map>
#include <vector>
#include <stack>

constexpr int N = 1e6 + 7;
constexpr int max = 1e9 + 7;
constexpr int min= -1e9 + 7;
int t[N];

int main()
{
    std::ios_base::sync_with_stdio(0);
    std::cin.tie(0);

    int n;
    std::cin >> n >> t[0];
    bool bul = 0;//1 akt ma byc wieksza
    //0 akt mniejszcze
    int gp = t[0];
    int dp = t[0];
    int wynik = 0;
    for (int i = 1; i < n; ++i)
    {
        std::cin >> t[i];
        if (bul == 0)
        {
            if (t[i] < gp)
            {
                gp = t[i];
                dp = t[i];
            }
            else
            {
                gp = max;
                dp = min;
                ++wynik;
            }
            bul = 1;
        }
        else
        {
            if (t[i] > dp)
            {
                gp = t[i];
                dp = t[i];
            }
            else
            {  
                gp = max;
                dp = min;
                ++wynik;
            }
            bul = 0;
        }
    }
    int gp2 = max;
    int dp2 = min;
    int wynik2 = 0;
    bool bul2 = 0;
    for (int i = 0; i < n; ++i)
    {
        if (bul2 == 0)
        {
            if (t[i] < gp2)
            {
                gp2 = t[i];
                dp2 = t[i];
            }
            else
            {
                gp2 = max;
                dp2 = min;
                ++wynik2;
            }
            bul2 = 1;
        }
        else
        {
            if (t[i] > dp2)
            {
                gp2 = t[i];
                dp2 = t[i];
            }
            else
            {
                gp2 = max;
                dp2 = min;
                ++wynik2;
            }
            bul2 = 0;
        }
    }

    std::cout << std::min(wynik, wynik2);
}