This is my method to swap two adjacent elements by adjusting only the links (and

Question

This is my method to swap two adjacent elements by adjusting only the links (and not the data) using a single linked list. But when I run the test program it is printing the list without the swap. I know I am not accessing the linked list when i swap so I am not sure what the test program code should look like in order for the swap to work.

Notes: beforep is an input parameter that represents the node before the two adjacent nodes that are to be swapped.

public class Problem1Swapping {

    public static void swapWithNext(Node beforeP) {
        Node p; //First Node to be swapped
        Node afterP;//Second Node to be swapped

        p = beforeP.next;
        afterP = p.next;

        p.next = afterP.next;
        beforeP.next = afterP;
        afterP.next = p;
    }

}

//Provided Node class to use for problem 1
    public class Node {

        public Object data;
        public Node next;

        public Node(Object data, Node next) {
            this.data = data;
            this.next = next;
        }
      
        @Override
        public String toString(){
            return this.data + "";         
        }
    }

public class Problem1SwappingTester {
  
    public static void main(String args[]){
      
        Node node1 = new Node(25, null);
        Node node2 = new Node(35, node1);
        Node node3 = new Node(46, node2);
        Node node4 = new Node(57, node3);
        Node node5 = new Node(68, node4);

        LinkedList list1 = new LinkedList();
        list1.add(node5);
        list1.add(node4);
        list1.add(node3);
        list1.add(node2);
        list1.add(node1);
      
        System.out.println(list1);
        Problem1Swapping.swapWithNext(node3);
        System.out.println(list1);
    }   
}

OUTPUT:

run:
[68, 57, 46, 35, 25]
[68, 57, 46, 35, 25]
BUILD SUCCESSFUL (total time: 0 seconds)

Explanation / Answer

Here, declared swap function with head node as parameter

void SwapWithNext(struct node *head)

{

    struct node *t = head;

    while (t != NULL && t->next != NULL)

    {

        /* Swap data of node with its next node's data */

        swap(&t->data, &t->next->data);

        t = t->next->next;

    }

}

void swap(int *x, int *y)

{

    int temp;

    temp = *x;

    *x = *y;

    *y = temp;

}

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.