In this tutorial, we are going to learn about MoveBefore() function in list package in go golang.
Function proto type:
func (l *List) MoveBefore(src_ele, dst_ele *Element)
MoveBefore() function:
MoveBefore() function moves src_ele node to before dst_ele node.
If src_ele and dst_ele nodes are same then list will not get modified.
Internal code of MoveBefore() function in list package:
func (l *List) MoveBefore(src_ele, dst_ele *Element) {
if src_ele.list != l || src_ele == dst_ele || dst_ele.list != l {
return
}
l.move(src_ele, dst_ele.prev)
}
Example to use MoveBefore() function in list:
package main
import (
"container/list"
"fmt"
)
func main() {
var ele, src_ele, dst_ele *list.Element
// Create a new list and insert elements in it.
l := list.New()
l.PushBack(1) // 1
l.PushBack(2) // 1 -> 2
l.PushBack(3) // 1 -> 2 -> 3
l.PushBack(4) // 1 -> 2 -> 3 -> 4
l.PushBack(5) // 1 -> 2 -> 3 -> 4 -> 5
fmt.Println("Print list before moving element")
for ele = l.Front(); ele != nil; ele = ele.Next() {
fmt.Println(ele.Value)
}
// Keep src_ele pointer variable at element with value 4
for src_ele = l.Front(); src_ele.Value != 4; src_ele = src_ele.Next() {}
// Keep dst_ele pointer variable at element with value 2
for dst_ele = l.Front(); dst_ele.Value != 2; dst_ele = dst_ele.Next() {}
// move element with value 4 to before element with value 2
l.MoveBefore(src_ele, dst_ele)
// Now list is: 1 -> 4 -> 2 -> 3 -> 5
fmt.Println("Print list after moving element")
for ele = l.Front(); ele != nil; ele = ele.Next() {
fmt.Println(ele.Value)
}
}
Output:
Print list before moving element
1
2
3
4
5
Print list after moving element
1
4
2
3
5
To learn more about golang, Please refer given below link:
https://www.techieindoor.com/go-lang-tutorial/
References:
https://golang.org/doc/
https://golang.org/pkg/
https://golang.org/pkg/fmt/
https://golang.org/pkg/fmt/#Println
https://golang.org/pkg/container/list/