Question

use java

There are n students in a class and n numbered chairs. The instructor has assigned a presentation for each student and is going to select the order of presentations by the following scheme. A number m is chosen. Beginning at seat number 1, she counts to m. The student sitting in that seat presents first.
Then she starts counting seats again, starting from the next seat, wrapping around at the end, and skipping any student who has already been selected, until m is again reached. This student presents next. The process continues until all students have been selected. For example, if there were 5
students and the instructor selected m=3, then the order would be (3,1,5,2,4).

Write an application program that will take n and m as input from the keyboard and output the order of presentations. This is what is usually referred to as a Josephus permutation. There are some mathematical tricks to finding the permutation quickly (or at least finding the last number of the sequence), but I want you to implement this by simulation using a queue to represent the data.
You should start with a queue containing the first n integers. Numbers are removed
from the queue and reinserted until you reach the mth number. The mth number is then removed and inserted into the result queue. This process is repeated until the initial queue is empty. Then you simply dequeue and print each item from the result queue.

For example, with our example of 5 students with m=3

Class queue	Result queue
1 2 3 4 5	(empty)
4 5 1 2	3
2 4 5	3 1
2 4	3 1 5
4	3 1 5 2
(empty)	3 1 5 2 4

So the resulting permutation, J(5,3) = {3,1,5,2,4}.

Answer 1

Here is the completed code for this problem. Using java’s built in Queue libraries to implement this. If you want this to be a custom made queue, let me know. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. If not, PLEASE let me know before you rate, I’ll help you fix whatever issues. Thanks

// JosephusProblem.java

import java.util.LinkedList;

import java.util.Queue;

import java.util.Scanner;

public class JosephusProblem {

      public static void main(String[] args) {

            // creating two queues, one for representing students in class, second

            // is for representing the order of presentations

            Queue<Integer> classQueue = new LinkedList<Integer>();

            Queue<Integer> resultQueue = new LinkedList<Integer>();

            // using a Scanner, reading the values for n and m

            Scanner scnr = new Scanner(System.in);

            System.out.print("Enter n and m: ");

            int n = scnr.nextInt();

            int m = scnr.nextInt();

            // adding numbers 1 to n to the class queue

            for (int i = 1; i <= n; i++) {

                  classQueue.add(i);

            }

            // looping until classQueue is empty

            while (!classQueue.isEmpty()) {

                  // looping for m-1 number of times

                  for (int i = 0; i < m - 1; i++) {

                        // removing front value from classQueue, adding to the rear

                        int value = classQueue.remove();

                        classQueue.add(value);

                  }

                  // removing m'th value into a variable

                  int removed = classQueue.remove();

                  // adding this value to the result queue

                  resultQueue.add(removed);

            }

            // now simply looping and printing result queue until it is empty

            System.out.print("The order: ");

            while (!resultQueue.isEmpty()) {

                  System.out.print(resultQueue.remove() + " ");

            }

            System.out.println();

      }

}

/*OUTPUT*/

Enter n and m: 5 3

The order: 3 1 5 2 4