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+# Linklist
+Linklist a linked list, whose node has a value and a pointer points to next node of the link.
+
+<div STYLE="page-break-after: always;"></div>
+
+## Source
+
+- [https://github.com/duke-git/lancet/blob/main/datastructure/link/singlylink.go](https://github.com/duke-git/lancet/blob/main/datastructure/link/singlylink.go)
+- [https://github.com/duke-git/lancet/blob/main/datastructure/link/doublylink.go](https://github.com/duke-git/lancet/blob/main/datastructure/link/doublylink.go)
+
+
+<div STYLE="page-break-after: always;"></div>
+
+## Usage
+```go
+import (
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+```
+
+<div STYLE="page-break-after: always;"></div>
+
+## Index
+
+### 1. SinglyLink
+
+
+
+- [NewSinglyLink](#NewSinglyLink)
+- [Values](#SinglyLink_Values)
+
+- [InsertAt](#SinglyLink_InsertAt)
+- [InsertAtHead](#SinglyLink_InsertAtHead)
+- [InsertAtTail](#SinglyLink_InsertAtTail)
+- [DeleteAt](#SinglyLink_DeleteAt)
+- [DeleteAtHead](#SinglyLink_DeleteAtHead)
+- [DeleteAtTail](#SinglyLink_DeleteAtTail)
+- [DeleteValue](#SinglyLink_DeleteValue)
+- [Reverse](#SinglyLink_Reverse)
+- [GetMiddleNode](#SinglyLink_GetMiddleNode)
+- [Size](#SinglyLink_Size)
+  
+- [IsEmpty](#SinglyLink_IsEmpty)
+- [Clear](#SinglyLink_Clear)
+- [Print](#SinglyLink_Print)
+
+
+
+
+<div STYLE="page-break-after: always;"></div>
+
+## Documentation
+
+### 1. SinglyLink
+SinglyLink a linked list, whose node has a value and a pointer points to next node of the link.
+
+### <span id="NewSinglyLink">NewSinglyLink</span>
+<p>Return a singly link(SinglyLink) instance</p>
+
+<b>Signature:</b>
+
+```go
+type LinkNode[T any] struct {
+	Value T
+	Next  *LinkNode[T]
+}
+type SinglyLink[T any] struct {
+	Head   *datastructure.LinkNode[T]
+	length int
+}
+func NewSinglyLink[T any]() *SinglyLink[T]
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+    fmt.Println(lk)
+}
+```
+
+
+
+### <span id="SinglyLink_Values">Values</span>
+<p>Return a slice of all node value in singly linklist</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) Values() []T
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    fmt.Println(lk.Values()) //[]int{1, 2, 3}
+}
+```
+
+
+
+
+### <span id="SinglyLink_InsertAt">InsertAt</span>
+<p>Insert value into singly linklist at index, index shoud be great or equal 0 and less or equal number of link nodes</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) InsertAt(index int, value T) error
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAt(0, 1)
+	lk.InsertAt(1, 2)
+	lk.InsertAt(2, 3)
+	lk.InsertAt(2, 4)
+
+    fmt.Println(lk.Values()) //[]int{1, 2, 4, 3}
+}
+```
+
+
+
+
+### <span id="SinglyLink_InsertAtHead">InsertAtHead</span>
+<p>Insert value into singly linklist at head(first) index</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) InsertAtHead(value T)
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtHead(1)
+	lk.InsertAtHead(2)
+	lk.InsertAtHead(3)
+
+    fmt.Println(lk.Values()) //[]int{3, 2, 1}
+}
+```
+
+
+
+
+### <span id="SinglyLink_InsertAtTail">InsertAtTail</span>
+<p>Insert value into singly linklist at tail(last) index</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) InsertAtTail(value T)
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    fmt.Println(lk.Values()) //[]int{1, 2, 3}
+}
+```
+
+
+
+### <span id="SinglyLink_DeleteAt">DeleteAt</span>
+<p>Delete value into singly linklist at index, index shoud be great or equal 0 and less or less than number of link nodes - 1</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) DeleteAt(index int) error
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+	lk.InsertAtTail(4)
+
+    err := lk.DeleteAt(3)
+
+    fmt.Println(err) //nil
+    fmt.Println(lk.Values()) //[]int{1, 2, 3}
+}
+```
+
+
+
+### <span id="SinglyLink_DeleteAtHead">DeleteAtHead</span>
+<p>Delete value in singly linklist at first index</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) DeleteAtHead() error
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+	lk.InsertAtTail(4)
+
+    err := lk.DeleteAtHead()
+    
+    fmt.Println(err) //nil
+    fmt.Println(lk.Values()) //[]int{2, 3, 4}
+}
+```
+
+
+
+
+### <span id="SinglyLink_DeleteAtTail">DeleteAtTail</span>
+<p>Delete value in singly linklist at last index</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) DeleteAtTail() error
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    err := lk.DeleteAtTail()
+    
+    fmt.Println(err) //nil
+    fmt.Println(lk.Values()) //[]int{1, 2}
+}
+```
+
+
+
+### <span id="SinglyLink_DeleteValue">DeleteValue</span>
+<p>Delete all `value` in singly linklist</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) DeleteValue(value T)
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    lk.DeleteValue(2)
+    fmt.Println(lk.Values()) //[]int{1, 3}
+}
+```
+
+
+
+
+### <span id="SinglyLink_Reverse">Reverse</span>
+<p>Reverse all nodes order in linkist</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) Reverse()
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    lk.Reverse()
+    fmt.Println(lk.Values()) //[]int{3, 2, 1}
+}
+```
+
+
+
+### <span id="SinglyLink_GetMiddleNode">GetMiddleNode</span>
+<p>Get the node at middle index of linkist</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) GetMiddleNode() *datastructure.LinkNode[T]
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    midNode := lk.GetMiddleNode()
+    fmt.Println(midNode.Value) //2
+}
+```
+
+
+
+### <span id="SinglyLink_Size">Size</span>
+<p>Get the number of nodes in linklist</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) Size() int
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    fmt.Println(lk.Size()) //3
+}
+```
+
+
+
+### <span id="SinglyLink_IsEmpty">IsEmpty</span>
+<p>Checks if linklist is empty or not</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) IsEmpty() bool
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+    fmt.Println(lk.IsEmpty()) //true
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    fmt.Println(lk.IsEmpty()) //false
+}
+```
+
+
+
+### <span id="SinglyLink_Clear">Clear</span>
+<p>Clear all nodes in the linklist, make it empty</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) Clear()
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+
+    lk.Clear()
+
+    fmt.Println(lk.Values()) //
+}
+```
+
+
+
+### <span id="SinglyLink_Print">Print</span>
+<p>Print all nodes info of linklist</p>
+
+<b>Signature:</b>
+
+```go
+func (link *SinglyLink[T]) Clear()
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    link "github.com/duke-git/lancet/v2/datastructure/link"
+)
+
+func main() {
+    lk := link.NewSinglyLink[int]()
+
+    lk.InsertAtTail(1)
+	lk.InsertAtTail(2)
+	lk.InsertAtTail(3)
+    
+    lk.Print() //[ &{Value:1 Pre:<nil> Next:0xc0000a4048}, &{Value:2 Pre:<nil> Next:0xc0000a4060}, &{Value:3 Pre:<nil> Next:<nil>} ]
+}
+```
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