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#include <bits/stdc++.h>
#include <chrono>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace chrono;
using namespace __gnu_pbds;
#pragma GCC optimize("Ofast,unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma,tune=native")
//#pragma GCC target("sse,sse2,sse3,mmx,abm,tune=native") // for szkopul and sio only
typedef long long lld;
typedef double lf;
typedef long double llf;
typedef pair<int,int> pii;
typedef pair<lld,lld> pll;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> oset;
#define For(i,s,a) for(lld i = (lld)s; i < (lld)a; ++i)
#define rpt(s, it) for(auto it = s.begin(); it != s.end(); ++it)
#define brpt(s, it) for(auto it = s.rend(); it != s.rbegin(); --it)
#define pb push_back
#define eb emplace_back
#define ff first
#define dd second
#define mp make_pair
#define all(x) (x).begin(), (x).end()
#define make_unique(x) (x).erase( unique(all(x)), (x).end())
#define popcnt(x) __builtin_popcount(x)
#define sz size()
#define time_since duration_cast< milliseconds >(system_clock::now().time_since_epoch())
 
template<typename Ta, typename Tb>
ostream & operator <<(ostream & os, pair<Ta, Tb> x){
    return os << x.ff << " " << x.dd;
}

const int N = 1e5 + 1;
int c[4][N], input[N];

int main(void) {
    int n;  
    scanf("%d", &n);
    For (i, 0, n)
        scanf("%d", &input[i]);
    c[2][0] = c[3][0] = 1;
    For (i, 1, n) {
        For (j, 0, 4)
            c[j][i] = 0x3f3f3f3f;
        c[0][i] = c[3][i - 1];
        c[1][i] = c[2][i - 1];
        if (input[i - 1] < input[i])
            c[0][i] = min(c[0][i], c[1][i - 1]);
        else if (input[i - 1] > input[i])
            c[1][i] = min(c[1][i], c[0][i - 1]);
        For (j, 2, 4)
            c[j][i] = min(c[j][i], min(1 + c[j ^ 1][i - 1], 1 + c[j ^ 3][i - 1]));
    }
    int wyn = 0x3f3f3f3f;
    For (i, 0, 4)
        wyn = min(wyn, c[i][n - 1]);
    printf("%d\n", wyn);
}