linked list

linkedlistsingle.go

package linkedlistsingle

import "fmt"

type node struct {
	Next  *node
	Value int
}

//LinkedList is a data structure for storing data in nodes with references to each other
type LinkedList struct {
	head *node
	tail *node
}

func (linked LinkedList) String() string {
	var result string
	for current := linked.head; current != nil; current = current.Next {
		result += fmt.Sprintf("%d-->", current.Value)
	}
	return result
}

//Add method on LinkedList which inserts an integer into the data structure
func (linked *LinkedList) Add(val int) {
	n := node{Value: val}
	if linked.head == nil {
		linked.head, linked.tail = &n, &n
	} else {
		linked.tail.Next = &n
		linked.tail = &n
	}
}

//Contains traverses list looking for paramter v, returns true if v is in list
func (linked *LinkedList) Contains(v int) bool {
	for current := linked.head; current != nil; current = current.Next {
		if current.Value == v {
			return true
		}
	}
	return false
}

//Remove node by value from linked list
func (linked *LinkedList) Remove(v int) bool {
	if linked.head == nil {
		return false
	}
	if linked.head.Value == v {
		if linked.head == linked.tail {
			linked.head, linked.tail = nil, nil
		} else {
			linked.head = linked.head.Next
		}
		return true
	}
	for current := linked.head; current.Next != nil; current = current.Next {
		if current.Next.Value == v {
			if linked.tail == current.Next {
				current.Next = nil
				linked.tail = current
			} else {
				current.Next = current.Next.Next
			}
			return true
		}
	}
	return false
}

//Reverse reverses the linked list
func (linked *LinkedList) Reverse() {
	var prev *node
	current := linked.head
	linked.tail = current
	for current != nil {
		next := current.Next
		current.Next = prev
		prev = current
		current = next
	}
	linked.head = prev
}