#include<bits/stdc++.h>
using namespace std;
#define max_n 500000
#define inf ((long long)1e13)
int n;
long long a[max_n+2];
long long sta[21][max_n+2];
long long sti[21][max_n+2];
int lg[max_n+2];
long long ans=0;
inline int querya(int l,int r){
	int lg=::lg[r-l+1];
	return max(sta[lg][l],sta[lg][r-(1<<lg)+1]);
}
inline int queryi(int l,int r){
	int lg=::lg[r-l+1];
	return min(sti[lg][l],sti[lg][r-(1<<lg)+1]);
}
int main(){
	#ifndef ONLINE_JUDGE
	freopen("P10144_1.in","r",stdin);
	freopen("P10144_1.out","w",stdout);
	#endif
	scanf("%d",&n);
	for(int i=1;i<=n;++i){scanf("%lld",a+i); a[i]<<=2;}
	for(int i=1;i<=n;++i){sta[0][i]=0; sti[0][i]=inf;}
	sti[0][1]=sti[0][n]=inf;
	for(int i=2;i<n;++i){
		long long l1=0,r1=inf,l2=0,r2=inf,l,r;
		if(a[i-1]<a[i])r1=(a[i-1]+a[i])/2;
		else l1=(a[i-1]+a[i])/2;
		if(a[i]>a[i+1])r2=(a[i]+a[i+1])/2;
		else l2=(a[i-1]+a[i])/2;
		l=max(l1,l2); r=min(r1,r2);
		if(l==0)sta[0][i]=r;
		if(r==inf)sti[0][i]=l;
	}
	for(int j=1;j<=20;++j){
		for(int i=1;i+(1<<j)-1<=n;++i){
			sta[j][i]=max(sta[j-1][i],sta[j-1][i+(1<<(j-1))]);
			sti[j][i]=min(sti[j-1][i],sti[j-1][i+(1<<(j-1))]);
		}
	}
	for(int l=1,r=2;l<n;++l){
		r=max(r,l+1);
		while(r+1<=n&&querya(l+1,r)<queryi(l+1,r))++r;
		ans+=r-l;
	}
	printf("%lld\n",ans);
	return 0;
}