The Josephus Problem

I am having a bit of trouble. The Josephus problem is where you have a circle of people, body_count people big (like, if body_count were 5, that means the circle is made up of 5 people). And another term, excuse_counter, is set to a number. Using this number we go around the circle elinimating people until one is left.

For instance, let's say the circle is made of 9 people, and we choose our excuse_counter to be 5:

5, 1, 7, 4, 3, 6, 9, 2, 8

We reloop around this circle nailing off the person we come to when we count to excuse_counter. Using the remaining people we count again, etc, until we are left with one man left.

However I am having a bit of trouble with the coding portion. It finds the first person alright, but from here it's all downhill:

Code:

---


person* pick_person(person *group, int excuse_counter, int body_count){
        person *temp = new person;
        temp -> position = 12345;
        temp -> next = group;
       
        person *previous = temp;
        person *current;
       
        for (int i = 1; i < body_count; i++){
               
                for (int x = 1; x <= excuse_counter; x++){

                        if (temp -> next -> next == NULL)
                                temp -> next = previous -> next;
                       
                       
                        else
                                temp = temp -> next;
                                       
                }
               
                cout << "\nPerson " << temp -> position << " is leaving...";
               
                current = temp;
               
                       
                while (previous -> next != current){
                        previous = previous -> next;
                }
                       
                previous -> next = current -> next;
                delete current;
                                                                   
        }       

return group;
} //end person *pick_person

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The struct:

Code:

---


struct person{
        int position;
        person *next;
};

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I know this is very close to working but it needs a push in the right direction. I am using a linklist

I would use a queue. I had to do this problem in college.

Also, would it be better to use a random number to choose which person who would be killed??

No the user decides the values

That and the problem states that we must use a linklist

well my approach to this would be a circular list. This can be rotated and nodes removed. I would think that a circular list will model a circle of people better

Try to find the trick to solving this problem fast without a
list.