Question

Write a method in java in a most basic way rotatelist that rotates an arraylist to the right by k steps. The
user will be asked to enter the arraylist and k in the program. For example :
if the input arraylist is [1,2,3,4,5,6,7] and k is 3, then the method will return
[5,6,7,1,2,3,4] .

Answer 1

import java.util.ArrayList;
import java.util.Arrays;

public class Rotate {

    public static void rotate(ArrayList<Integer> list, int k) {
        for (int i = 0; i < k; i++) {
            int n = list.get(list.size()-1);
            for (int j = list.size()-1; j > 0; j--) {
                list.set(j, list.get(j-1));
            }
            list.set(0, n);
        }
    }

    public static void main(String[] args) {
        ArrayList<Integer> list = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7));
        rotate(list, 3);
        System.out.println(list);
    }
}