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#include<bits/stdc++.h>
#define INF 1e9+7
using namespace std;
pair<int, int> dp[50100][2];
int t[50100];
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin>>n;
	for(int i=0;i<n;i++)
	cin>>t[i];
	dp[0][0] = {t[0], 0};
	dp[0][1] = {t[0], 0};
	for(int i=1;i<n;i++)
	{
		if(t[i] > dp[i-1][0].first)
		dp[i][1] = {t[i], dp[i-1][0].second};
		else
		dp[i][1] = {INF, dp[i-1][0].second+1};
		if(t[i] < dp[i-1][1].first)
		dp[i][0] = {t[i], dp[i-1][1].second};
		else
		dp[i][0] = {-INF, dp[i-1][1].second+1};
	}
	cout<<min(dp[n-1][0].second, dp[n-1][1].second);
}