javalab22.java

import java.util.*;

public class javalab22 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        ArrayList <String> List = new ArrayList<>();
        System.out.print("Enter number of elements in the string type List: ");
        int n = sc.nextInt();
        String st;
        sc.nextLine();
        for(int i = 0;i < n; i++){
            System.out.println(" Enter element " + (i+1) + ":");
            st = sc.nextLine();
            List.add(st);
        }
        Swap(List);
        System.out.println("List after swapping of elelments: ");
        System.out.println(List);
    }

    static void Swap(ArrayList<String> list){
        String st;
        for(int i = 0;i < list.size()-1; i+=2){
            // st = list.get(i);
            // list.set(i, list.get(i + 1));
            // list.set(i + 1, st);
            Collections.swap(list, i, i+1);
        }
    }
}