Question

Write a program to swap mth and nth elements of a linked list.

Code needed in java.

Answer 1

Code in java programming language:

 
class Node 
{ 
    int Data; 
    Node next; 
    Node(int data) 
    { 
        Data = data; 
        next = null; 
    } 
} 
  
class Test 
{ 
    Node head; 
    public void swap(int x, int y) 
    { 
        if (x == y) return; 
  
       Node preX = null, currentX = head; 
        while (currentX != null && currentX.Data != x) 
        { 
            preX = currentX; 
            currentX = currentX.next; 
        } 
  
        Node preY = null, currentY = head; 
        while (currentY != null && currentY.Data != y) 
        { 
            preY = currentY; 
            currentY = currentY.next; 
        } 
  
        if (currentX == null || currentY == null) 
            return; 
  
        if (preX != null) 
            preX.next = currentY; 
        else 
            head = currentY; 
  
        if (preY != null) 
            preY.next = currentX; 
        else 
        head = currentX; 
  
        Node temp = currentX.next; 
        currentX.next = currentY.next; 
        currentY.next = temp; 
    } 
  
    public void push(int new_data) 
    { 
        Node new_Node = new Node(new_data); 
  
        new_Node.next = head; 
  
        head = new_Node; 
    } 
  
    public void print() 
    { 
        Node tNode = head; 
        while (tNode != null) 
        { 
            System.out.print(tNode.Data+" "); 
            tNode = tNode.next; 
        } 
    } 
  
    public static void main(String[] args) 
    { 
        Test linkList = new Test(); 
        linkList.push(70); 
        linkList.push(60); 
        linkList.push(50); 
        linkList.push(40); 
        linkList.push(30); 
        linkList.push(20); 
        linkList.push(10);
  
        System.out.print("\n Linked list :"); 
        linkList.print(); 
  
        linkList.swap(40, 30); 
  
        System.out.print("\n Sorted Linked list : "); 
        linkList.print(); 
    } 
}

Output Screen Shot:

Thank you................