[DP] poj1836

 

/* 題意知道N個人身高 h[1..n]; 要求是的形成一個 h[1]<h[2]<...<h[x]>=h[x+1]>h[x+2]>..的隊列 且出列的人最少 2個最長升序列，枚舉中間2個點。 */ 
import java.util.*;
import java.math.*;
import java.io.*;
public class Main 
{
	static int MIN(int a,int b){return (a>b)? b:a;}
	static int MAX(int a,int b){return (a<b)? b:a;}
	static int Max_Int=200000000;
	public static void main(String[] args)
	{
		Scanner cin=new Scanner(System.in);
		int n;
		double h[]=new double[1100];
		int f1[]=new int [1100],f2[]=new int [1100];
		while(cin.hasNextInt())
		{
			n=cin.nextInt();
			for(int i=1;i<=n;i++)
				h[i]=cin.nextDouble();
			for(int i=1;i<=n;i++)
				f1[i]=1;
			for(int i=2;i<=n;i++)
				for(int j=1;j<i;j++)
					if(h[i]>h[j] && f1[i]<f1[j]+1)
						f1[i]=f1[j]+1;
			for(int i=1;i<=n;i++)
				f2[i]=1;
			for(int i=n-1;i>=1;i--)
				for(int j=n;j>i;j--)
					if(h[i]>h[j] && f2[i]<f2[j]+1)
						f2[i]=f2[j]+1;
			int Max=0;
			for(int i=1;i<n;i++)
				for(int j=i+1;j<=n;j++)
				Max=MAX(f1[i]+f2[j],Max);
			System.out.println(n-Max);
		}
	}
	static int readInt() 
	{
        int res = 0, c = 0;
        do{
            try{
                c = System.in.read();
                if (c == -1) return -1;
                if (c == '-') return -readInt();
            } catch (Exception e) {}
        } while (c < '0' || c > '9');
        do{
            res = res * 10 + c - '0';
            try 
            {
                c = System.in.read();
            } 
            catch (Exception e) {}
        } while ('0' <= c && c <= '9');
        return res;
    }

}