#include<stdio.h>
#include<string.h>

const int oo=-1000000000;

int n,ans,a[1001],f[1001][2];

inline int max(int a,int b){return a>b?a:b;}

int main()
{
	freopen("missilea.in","r",stdin);
	freopen("missilea.out","w",stdout);
	int i,j;a[0]=oo;for(scanf("%d",&n);n;scanf("%d",&n))
	{
		memset(f,0,sizeof(f));ans=0;for(i=1;i<=n;i++)
		{scanf("%d",&a[i]);for(j=0;j<i;j++){
		if(a[j]<a[i])f[i][0]=max(f[i][0],f[j][1]+1);
		if(a[j]>a[i])f[i][1]=max(f[i][1],f[j][0]+1);
		}}for(i=1;i<=n;i++)ans=max(f[i][0],f[i][1]);
		printf("%d\n",ans);
	}
	return 0;
}