/*
TASK:psort
LANG:C++
*/
#include<iostream>
using namespace std;

#define maxn 50000

int n;
int a1[maxn];
int a2[maxn];
int sol(int mi,int *a)
{
    int i,res;
	int ls,rs,it,j;
    ls=mi;
	rs=mi+1;
	res=0;
	while(ls>0 || rs<n)
	{
		
		while(a[ls-1]<a[ls] && ls>0)ls--;
		while(a[rs]>a[rs-1] && rs<n)rs++;
		if(ls>0)
		{
			i=mi;
			while(a[i]<a[ls-1] && i<rs)i++;
			it=a[ls-1];
			j=ls-1;
			while(j<(i-1))a[j]=a[++j];
			a[i]=it;
			ls--;
			mi--;
			res++;
		}
		if(rs<n)
		{
			i=mi;
			while(a[i]>a[rs] && i>0)i--;
			it=a[rs];
			j=rs;
			while(j>i)
				a[j]=a[--j];
			a[i]=it;
			rs++;
 			mi++;
			res++;
		}
	}
	return res;
}

int main()
{
	cin>>n;
	int i,res;
	int m1,m2;
	for(i=0;i<n;i++)
	{
		cin>>a1[i];
		a2[i]=a1[i];
		if(a1[i]==(n/2))
			m1=i;
		if(a1[i]==(n/2+1))
            m2=i;
	}
	res=sol(m1,a1);
	m1=sol(m2,a2);
	if(m1<res)res=m1;
	cout<<res<<endl;
	return 0;
}
