#include <iostream>
#include <algorithm>
#include <cmath>
#include <string>
#include <cstring>
#include <cstdio>
using namespace std;

int n,a[10005];
int ans=0;
int main(){
	scanf("%d",&n);
	for(int i=1;i<=n;i++)
		scanf("%d",&a[i]);
	for(int i=1;i<=n;i++){
		if(a[i]<a[i-1]){
			if(a[i+1]<a[i])
				continue ;
			else
				ans++;
		}
	}
	cout<<ans-1<<endl;
	return 0;
}

rt