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#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x)
#else
#define debug(...) {}
#endif

int main() {
	cin.tie(0)->sync_with_stdio(0);
  int n;
  cin >> n;
  vector t(n, 0);
  REP (i, n)
    cin >> t[i];
  vector dp(n, vector (2, vector (2, 0)));
  dp[0][1][0] = dp[0][1][1] = 1;
  FOR (i, 1, n - 1) {
    dp[i][1][0] = min(dp[i - 1][1][1], dp[i - 1][0][1]) + 1;
    dp[i][1][1] = min(dp[i - 1][1][0], dp[i - 1][0][0]) + 1;
    dp[i][0][0] = dp[i - 1][1][1];
    if (t[i] > t[i - 1])
      dp[i][0][0] = min(dp[i][0][0], dp[i - 1][0][1]);
    dp[i][0][1] = dp[i - 1][1][0];
    if (t[i] < t[i - 1])
      dp[i][0][1] = min(dp[i][0][1], dp[i - 1][0][0]);
  }
  int odp = n;
  REP (i, 2)
    REP (j, 2)
      odp = min(odp, dp[n - 1][i][j]);
  cout << odp << endl;
}