Golang Program to add the first node in a given linked list.

Example

Approach to solve this problem

Step 1 − Define a method that accepts the head of the linked list.

Step 2 − If head == nil, create a new node and return that node.

Step 3 − If head is not nil, then update the head of the input linked list.

Example

 Live Demo

package main import "fmt" type Node struct {    value int    next *Node } func NewNode(value int, next *Node) *Node{    var n Node    n.value = value    n.next = next    return &n } func TraverseLinkedList(head *Node){    temp := head    for temp != nil {       fmt.Printf("%d ", temp.value)       temp = temp.next    }    fmt.Println() } func AddFirstNode(head *Node, data int) *Node{    if head == nil{       head = NewNode(data, nil)       return head    }    newNode := NewNode(data, nil)    newNode.next = head    return newNode } func main(){    head := NewNode(30, NewNode(10, NewNode(40, NewNode(40, nil))))    fmt.Printf("Input Linked list is: ")    TraverseLinkedList(head)    head = AddFirstNode(head, 5)    fmt.Printf("After adding first node, linked list is: ")    TraverseLinkedList(head) }

Output

Input Linked list is: 30 10 40 40 After adding first node, linked list is: 5 30 10 40 40