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#include<bits/stdc++.h>
using namespace std;
typedef long long ll;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ///*
    ll n; cin >> n;
    vector<ll> records(n), variability(n-1);
    for(ll i = 0; i < n; i++){
        cin >> records[i];
        if(i > 0){
            if(records[i-1] < records[i]){
                variability[i-1] = 1;
            }
            else if(records[i-1] == records[i]){
                variability[i-1] = 0;
            }
            else{
                variability[i-1] = -1;
            }

        }
    }
    //*/
    /*
    ll n = 11;
    vector<ll> records = {-8, -6, 6, 6, -1, -4, -2, -7, 10, 6, -9}, variability(10);
    for(ll i = 0; i < n; i++){
        //cin >> records[i];
        if(i > 0){
            if(records[i-1] < records[i]){
                variability[i-1] = 1;
            }
            else if(records[i-1] == records[i]){
                variability[i-1] = 0;
            }
            else{
                variability[i-1] = -1;
            }

        }
    }
    */
    /*
    for(ll i = 0; i < n-1; i++){
        cout << variability[i] << " ";
    }
    cout << "\n";
    */

    ll count_1 = 0, i = 1, prev_direction = variability[0];

    if(variability[0] == 0){
        count_1++;
        prev_direction = 1;
        variability[0] = 1;
    }

    while(i < n-1){
        if(prev_direction != ((ll) pow(-1, variability[i])) * (variability[i])){
            count_1 += 1;
            i += 2;
            continue;
        }
        prev_direction = variability[i];
        i += 1;
    }

    ll count_2 = 1;
    
    prev_direction = ((ll) pow(-1, variability[0])) * (variability[0]);
    i = 1;
    while(i < n-1){
        if(prev_direction != ((ll) pow(-1, variability[i])) * (variability[i])){
            count_2 += 1;
            i += 2;
            continue;
        }
        prev_direction = variability[i];
        i += 1;
    }
    
    cout << min(count_1, count_2) << "\n";

    return 0;
}