#include<fstream>
using namespace std;
int v[5009],n,minim;
int l[5009],poz[5009],incepe[5009];
void minimul();
void solve();
int main()
{
	ifstream fin("subsir2.in");
	ofstream fout("subsir2.out");
	fin>>n;
	int i;
	for(i=1;i<=n;i++)
	   fin>>v[i],l[i]=n,poz[i]=-1;
	solve();
	minimul();
	fout<<minim;
	return 0;
}   
void solve()
{
	int i,j;
	l[1]=1;
	for(i=2;i<=n;i++)
	{
		int val=-1000000;
		for(j=i-1;j>=1;j--)
			if(v[j]<=v[i])
			{	
				if(v[j]>val)
				{
				    if(l[j]+1<l[i])
				        l[i]=l[j]+1,poz[i]=j;
				    val=v[j];
				}    
			    incepe[j]=1;
			}
		if(l[i]==n)
		   l[i]=1;	
	}
			 
			
	
}
void minimul()
{
	int i;
	minim=n;
	for(i=1;i<=n;i++)
		if(l[i]<minim && incepe[i]!=1)
			minim=l[i];
}