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#include <bits/stdc++.h>
using namespace std;
constexpr int LIM = 5e4;
int dp[LIM + 10][4];
int tab[LIM + 10];
int main() {
    int n;
    scanf("%d", &n);
    for(int i = 1; i <= n; i++) {
        scanf("%d", &tab[i]);
    }
    dp[1][0] = 1;
    dp[1][1] = 1;
    for(int i = 2; i <= n; i++) {
        dp[i][0] = min(dp[i - 1][1], dp[i - 1][2]) + 1;
        dp[i][1] = min(dp[i - 1][0], dp[i - 1][3]) + 1;
        if(tab[i] < tab[i - 1]) {
            dp[i][2] = min(dp[i - 1][0], dp[i - 1][3]);
        }
        else {
            dp[i][2] = dp[i - 1][0];
        }
        if(tab[i] > tab[i - 1]) {
            dp[i][3] = min(dp[i - 1][1], dp[i - 1][2]);
        }
        else {
            dp[i][3] = dp[i - 1][1];
        }
    }
    printf("%d\n", min({dp[n][0], dp[n][1], dp[n][2], dp[n][3]}));
}