C# | Find the last node in LinkedList<T> containing the specified value

LinkedList<T>.FindLast(T) method is used to find the last node that contains the specified value.

Syntax:

public System.Collections.Generic.LinkedListNode<T> FindLast (T value);

Here, value is the value to locate in the LinkedList.

Return Value: This method returns the last LinkedListNode<T> that contains the specified value, if found, otherwise, null.

Below given are some examples to understand the implementation in a better way:

Example 1:

// C# code to find the last node
// that contains the specified value
using System;
using System.Collections;
using System.Collections.Generic;

class GFG {

    // Driver code
    public static void Main()
    {
        // Creating a LinkedList of Strings
        LinkedList<String> myList = new LinkedList<String>();

        // Adding nodes in LinkedList
        myList.AddLast("A");
        myList.AddLast("B");
        myList.AddLast("C");
        myList.AddLast("D");
        myList.AddLast("E");

        // Finding the last node that
        // contains the specified value
        LinkedListNode<String> temp = myList.Find("D");

        Console.WriteLine(temp.Value);
    }
}

Output:

D

Example 2:

// C# code to find the last node
// that contains the specified value
using System;
using System.Collections;
using System.Collections.Generic;

class GFG {

    // Driver code
    public static void Main()
    {
        // Creating a LinkedList of Integers
        LinkedList<int> myList = new LinkedList<int>();

        // Adding nodes in LinkedList
        myList.AddLast(5);
        myList.AddLast(7);
        myList.AddLast(9);
        myList.AddLast(11);
        myList.AddLast(12);

        // Finding the last node that
        // contains the specified value
        LinkedListNode<int> temp = myList.Find(2);

        Console.WriteLine(temp.Value);
    }
}

Runtime Error:

Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object

Note:

• The LinkedList is searched backward starting at Last and ending at First.
• This method performs a linear search. Therefore, this method is an O(n) operation, where n is Count.

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.linkedlist-1.findlast?view=netframework-4.7.2