package main
import (
"fmt"
)
type Node struct {
value int
next *Node
}
func NewNode(val int) Node {
return Node{value: val, next : nil}
}
type MyLinklist struct{
head *Node
tail *Node
length int
}
func NewLinklist(value int) MyLinklist {
newNode := NewNode(value)
return MyLinklist{ head: &newNode, tail: &newNode, length: 1}
}
func (list *MyLinklist) append(value int) MyLinklist {
newNode := NewNode(value)
list.tail.next = &newNode
list.tail = &newNode
list.length++
return *list
}
func (list *MyLinklist) prepend(value int) MyLinklist {
newNode := Node{value: value, next : nil}
newNode.next = list.head
list.head = &newNode
list.length++
return *list
}
func (list *MyLinklist) insert(index, value int) (MyLinklist, error) {
if index < 0 || index > list.length {
return *list, fmt.Errorf("invalid input index should be in 0 and %d", list.length)
}
if index == 0 {
return list.prepend(value), nil
} else if index == list.length {
return list.append(value), nil
}
//get leader node at index
leader := list.traverseToIndexNode(index-1)
newNode := NewNode(value)
newNode.next = leader.next
leader.next = &newNode
list.length++
return *list, nil
}
func (list *MyLinklist) remove(index int) (MyLinklist, error) {
if index < 0 || index > list.length {
return *list, fmt.Errorf("invalid input index should be in 0 and %d", list.length)
}
if index == 0 {
list.head = list.head.next
return *list, nil
}
//get leader node
leaderNode := list.traverseToIndexNode(index-1)
fmt.Printf("\n remove node at %d , leader is : %v", index, leaderNode)
nodeToRemove := leaderNode.next
leaderNode.next = nodeToRemove.next
return *list, nil
}
func (list *MyLinklist) reverse() MyLinklist {
curr := list.head
list.tail = list.head
var prevNode *Node
var nextNode *Node
for curr != nil {
nextNode = curr.next
curr.next = prevNode
prevNode = curr
curr = nextNode
}
//At last point currHead to Prev
list.head = prevNode
return *list
}
//return node at index
func(list *MyLinklist) traverseToIndexNode(index int) *Node {
idxNode := list.head
c := 0
for c < index {
idxNode = idxNode.next
c++
}
return idxNode
}
func(list *MyLinklist) print() {
head := list.head
for head != nil {
fmt.Printf("%d \t", head.value)
head = head.next
}
}
func main() {
list := NewLinklist(5)
list.append(12)
list.append(10)
list.prepend(15)
list.prepend(1)
list.print()
_, err := list.remove(2)
if err != nil {
fmt.Println("insert error: ", err)
}
fmt.Println("\nafter remove node at index 2")
list.print()
_, err = list.insert(1, 100)
if err != nil {
fmt.Println("insert error: ", err)
}
fmt.Printf("\nafter insert node value %d at index %d \n", 100, 1)
list.print()
list.reverse()
fmt.Println("\n reverse list")
list.print()
}
package main
import (
"fmt"
)
type Node struct {
value int
next *Node
prev *Node
}
func NewNode(val int) Node {
return Node{value: val, next : nil, prev : nil}
}
type MyDoubleLinklist struct{
head *Node
tail *Node
length int
}
func NewMyDoubleLinklist(value int) MyLinklist {
newNode := NewNode(value)
return MyLinklist{ head: &newNode, tail: &newNode, length: 1}
}
func (list *MyDoubleLinklist) append(value int) MyDoubleLinklist {
currTailNode := list.tail
newNode := NewNode(value)
list.tail.next = &newNode
list.tail = &newNode
list.tail.prev = currTailNode
list.length++
return *list
}
func (list *MyDoubleLinklist) prepend(value int) MyDoubleLinklist {
newNode := NewNode(value)
newNode.next = list.head
list.head = &newNode
list.length++
return *list
}
func (list *MyDoubleLinklist) insert(index, value int) (MyDoubleLinklist, error) {
if index < 0 || index > list.length {
return *list, fmt.Errorf("invalid input index should be in 0 and %d", list.length)
}
if index == 0 {
return list.prepend(value), nil
} else if index == list.length {
return list.append(value), nil
}
//get leader node at index
leader := list.traverseToIndexNode(index-1)
newNode := NewNode(value)
newNode.next = leader.next
leader.next = &newNode
list.length++
return *list, nil
}
func (list *MyDoubleLinklist) remove(index int) (MyDoubleLinklist, error) {
if index < 0 || index > list.length {
return *list, fmt.Errorf("invalid input index should be in 0 and %d", list.length)
}
if index == 0 {
list.head = list.head.next
return *list, nil
}
//get leader node
leaderNode := list.traverseToIndexNode(index-1)
fmt.Printf("\n remove node at %d , leader is : %v", index, leaderNode)
nodeToRemove := leaderNode.next
leaderNode.next = nodeToRemove.next
return *list, nil
}
//return node at index
func(list *MyDoubleLinklist) traverseToIndexNode(index int) *Node {
idxNode := list.head
c := 0
for c < index {
idxNode = idxNode.next
c++
}
return idxNode
}
func(list *MyDoubleLinklist) print() {
head := list.head
for head != nil {
fmt.Printf("%d \t", head.value)
head = head.next
}
}
func(list *MyDoubleLinklist) printReverse() {
tail := list.tail
for tail != nil {
fmt.Printf("%d \t", tail.value)
tail = tail.prev
}
}
func main() {
list := NewMyDoubleLinklist(5)
list.append(12)
list.append(10)
list.prepend(15)
list.prepend(1)
list.print()
list.printReverse()
// _, err := list.remove(2)
// if err != nil {
// fmt.Println("insert error: ", err)
// }
// fmt.Println("\nafter remove node at index 2")
//list.printReverse()
// _, err = list.insert(1, 100)
// if err != nil {
// fmt.Println("insert error: ", err)
// }
// fmt.Printf("\nafter insert node value %d at index %d \n", 100, 1)
// list.print()
}
