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#include <iostream>
#include <string.h>

using namespace std;


int ornitolog(long long int *arr, int n) {
    int doo[n] = {0}, dont[n] = {0};
    doo[0] = 1;
    bool increase = true;
    for(int i = 1; i < n; ++i) {
        doo[i] = min(doo[i - 1], dont[i - 1]) + 1;
        dont[i] = min(doo[i - 1], ((arr[i - 1] < arr[i] && increase) || (arr[i - 1] > arr[i] && !increase)) ? dont[i - 1] : doo[i]);
        increase = !increase;
    }
    int res = dont[n - 1];
    for(int i = 0; i < n; ++i) {
        doo[i] = 0;
        dont[i] = 0;
    }
    doo[0] = 1;
    increase = false;
    for(int i = 1; i < n; ++i) {
        doo[i] = min(doo[i - 1], dont[i - 1]) + 1;
        dont[i] = min(doo[i - 1], ((arr[i - 1] < arr[i] && increase) || (arr[i - 1] > arr[i] && !increase)) ? dont[i - 1] : doo[i]);
        increase = !increase;
    }
    return min(res, dont[n - 1]);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n;
    cin >> n;
    long long int arr[n];
    for(int i = 0; i < n; ++i)
        cin >> arr[i];
    printf("%d", ornitolog(arr, n));
    return 0;
}