Unit 7 Application

import java.util.ArrayList;
import java.util.Collections;

ArrayList<Integer> numbers = new ArrayList<>(Arrays.asList(1,2,3,4,20,30,101,72,23,31,90,66));

Collections.sort(numbers);
Collections.reverse(numbers);


System.out.println("in decending order: " + numbers);

public static void swap_firstANDlast(){
    Integer temp = numbers.get(0);
    int last_index = numbers.size()-1; 
    numbers.set(0, numbers.get(last_index));
    numbers.set(last_index, temp);
    System.out.println("first and last element flipped while decending: " + numbers);
}
swap_firstANDlast()

in decending order: [101, 90, 72, 66, 31, 30, 23, 20, 4, 3, 2, 1]
first and last element flipped while decending: [1, 90, 72, 66, 31, 30, 23, 20, 4, 3, 2, 101]

import java.util.ArrayList;
import java.util.Collections; 


ArrayList<Integer> numbers2 = new ArrayList<>(Arrays.asList(1,2,3,4,20,30,101,72,23,31,90,66));

public void status(ArrayList<Integer> list){

ArrayList<Integer> numbers_acending = (ArrayList<Integer>)numbers2.clone();
Collections.sort(numbers_acending);
System.out.println(numbers_acending);

ArrayList<Integer> numbers_decending = (ArrayList<Integer>)numbers_acending.clone();
Collections.reverse(numbers_decending);
System.out.println(numbers_decending);

if (numbers_acending == numbers2){
    System.out.println("acending");
}
else if (numbers_decending == numbers2){
    System.out.println("decending");
}
else{
    System.out.println("neither");
}

}
//System.out.print(numbers_decending);

System.out.println(numbers2);

status(numbers2);

[1, 2, 3, 4, 20, 30, 101, 72, 23, 31, 90, 66]
[1, 2, 3, 4, 20, 23, 30, 31, 66, 72, 90, 101]
[101, 90, 72, 66, 31, 30, 23, 20, 4, 3, 2, 1]
neither