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#include<bits/stdc++.h>
using namespace std;
#define rep(a, b) for(int a = 0; a < (b); ++a)
const int LIM=5e4+7;
int dp[LIM][3][2], T[LIM];
int main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  int n;
  cin >> n;
  rep(i, n+1) dp[i][1][1]=dp[i][2][0]=LIM;
  for(int i=1; i<=n; ++i) {
    cin >> T[i];
    dp[i][1][0]=min(dp[i-1][0][1], dp[i-1][2][1])+1;
    dp[i][2][1]=min(dp[i-1][0][0], dp[i-1][1][0])+1;
    dp[i][0][0]=dp[i-1][2][1];
    if(i==1 || 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(i==1 || T[i]>T[i-1]) dp[i][0][1]=min(dp[i][0][1], dp[i-1][0][0]);
  }
  int ans=LIM;
  rep(i, 3) rep(j, 2) ans=min(ans, dp[n][i][j]);
  cout << ans << '\n';
}