C# program to remove the first occurrence of a node in a Linked List

The LinkedList class in C# provides an efficient way to store and manipulate collections of data. When you need to remove the first occurrence of a specific node from a LinkedList, you can use the Remove() method, which searches for the specified value and removes its first occurrence.

Syntax

The syntax for removing the first occurrence of a node from a LinkedList is −

bool result = linkedList.Remove(value);

Parameters

• value − The value to remove from the LinkedList. The method removes the first node that contains this value.

Return Value

The Remove()bool value −

• true − If the node was found and removed successfully.

• false − If the value was not found in the LinkedList.

Example

using System;
using System.Collections.Generic;

class Demo {
    static void Main() {
        string[] students = {"Katie", "Jennifer", "Amy", "Vera"};
        LinkedList<string> list = new LinkedList<string>(students);
        
        Console.WriteLine("Original LinkedList:");
        foreach (var stu in list) {
            Console.WriteLine(stu);
        }
        
        // removing the first occurrence of "Vera"
        bool removed = list.Remove("Vera");
        Console.WriteLine("\nRemoval successful: " + removed);
        
        Console.WriteLine("\nLinkedList after removing first occurrence of 'Vera':");
        foreach (var stu in list) {
            Console.WriteLine(stu);
        }
    }
}

The output of the above code is −

Original LinkedList:
Katie
Jennifer
Amy
Vera
Removal successful: True
LinkedList after removing first occurrence of 'Vera':
Katie
Jennifer
Amy

Removing From LinkedList with Duplicate Values

When a LinkedList contains duplicate values, the Remove() method removes only the first occurrence −

using System;
using System.Collections.Generic;

class Demo {
    static void Main() {
        string[] names = {"John", "Alice", "John", "Bob", "John"};
        LinkedList<string> list = new LinkedList<string>(names);
        
        Console.WriteLine("Original LinkedList:");
        foreach (var name in list) {
            Console.WriteLine(name);
        }
        
        // removing first occurrence of "John"
        bool removed = list.Remove("John");
        Console.WriteLine("\nFirst 'John' removed: " + removed);
        
        Console.WriteLine("\nLinkedList after removing first occurrence of 'John':");
        foreach (var name in list) {
            Console.WriteLine(name);
        }
    }
}

The output of the above code is −

Original LinkedList:
John
Alice
John
Bob
John
First 'John' removed: True
LinkedList after removing first occurrence of 'John':
Alice
John
Bob
John

Handling Non-Existent Values

When you try to remove a value that doesn't exist in the LinkedList, the Remove() method returns false −

using System;
using System.Collections.Generic;

class Demo {
    static void Main() {
        string[] students = {"Katie", "Jennifer", "Amy"};
        LinkedList<string> list = new LinkedList<string>(students);
        
        Console.WriteLine("Attempting to remove 'David' from the list:");
        bool removed = list.Remove("David");
        Console.WriteLine("Removal successful: " + removed);
        
        Console.WriteLine("\nLinkedList remains unchanged:");
        foreach (var stu in list) {
            Console.WriteLine(stu);
        }
    }
}

The output of the above code is −

Attempting to remove 'David' from the list:
Removal successful: False
LinkedList remains unchanged:
Katie
Jennifer
Amy

Conclusion

The Remove() method in C# LinkedList efficiently removes the first occurrence of a specified value and returns a boolean indicating success. This method is useful when you need to remove specific elements while preserving the order of remaining nodes in the linked list.