第四题，降序或升序最小的取法

import java.util.ArrayList;
import java.util.Scanner;

public class Main {
    private static int min = Integer.MAX_VALUE;
    public static void main(String[] args) {
        Scanner scan =new Scanner(System.in);
        int n =scan.nextInt();
        min=n;
        int[] list =new int[n];
        for(int i =0;i<n;i++) {
            list[i]=scan.nextInt();
        }
        search(list,0);
        System.out.println(min);
    }
    private static void search(int[] integers,int count) {
        count++;
        if(count>min)
            return;

        ArrayList<Integer> copy =new ArrayList<Integer>();
        for(Integer i :integers) {
            copy.add(i);
        }
        //升序规则 
        for(int i=integers.length-1;i>=0;i--) {
            if(i==0) {
                if(integers[i]>Integer.MIN_VALUE) {
                    copy.remove(i);
                }
            }else 
            if(integers[i]>integers[i-1]) {
                copy.remove(i);
            }
        }
        if(copy.size()==0) {
            if(count<min) {
                min=count;
            }
            return;
        }
        int[] copyArray = new int[copy.size()];
        for(int i =0;i<copy.size();i++) {
            copyArray[i]=copy.get(i);
        }
        search(copyArray,count);
        copy.clear();
        for(Integer i :integers) {
            copy.add(i);
        }
        //降序规则
        //升序规则 
        for(int i=integers.length-1;i>=0;i--) {
            if(i==0) {
                if(integers[i]<Integer.MAX_VALUE) {
                    copy.remove(i);
                }
            }else
            if(integers[i]<integers[i-1]) {
                copy.remove(i);
            }
        }
        if(copy.size()==0) {
            if(count<min) {
                min=count;
            }
            return;
        }
        copyArray = new int[copy.size()];
        for(int i =0;i<copy.size();i++) {
            copyArray[i]=copy.get(i);
        }
        search(copyArray,count);    
    }
}