public/subjects/sortlistinsert/README.md

sortlistinsert

Instructions

Create a function named SortListInsert, which accepts a pointer to the head of a sorted linked list and an integer.

The function should insert a new element into the list, with its Data set to the value of the integer. The element should be inserted so that the linked list remains sorted in ascending order by Data. The function should return the head of the list.

Your function will only be tested with sorted linked lists.

Expected function and structure

func SortListInsert(l *NodeI, data_ref int) *NodeI{

}

You have already defined the NodeI structure in the listsort exercise.

Usage

Here is a possible program to test your function :

package main

import (
	"fmt"

	"piscine"
)

func PrintList(l *piscine.NodeI) {
	it := l
	for it != nil {
		fmt.Print(it.Data, " -> ")
		it = it.Next
	}
	fmt.Print(nil, "\n")
}

func listPushBack(l *piscine.NodeI, data int) *piscine.NodeI {
	n := &piscine.NodeI{Data: data}

	if l == nil {
		return n
	}
	iterator := l
	for iterator.Next != nil {
		iterator = iterator.Next
	}
	iterator.Next = n
	return l
}

func main() {

	var link *piscine.NodeI

	link = listPushBack(link, 1)
	link = listPushBack(link, 4)
	link = listPushBack(link, 9)

	PrintList(link)

	link = piscine.SortListInsert(link, -2)
	link = piscine.SortListInsert(link, 2)
	PrintList(link)
}

And its output :

$ go run .
1 -> 4 -> 9 -> <nil>
-2 -> 1 -> 2 -> 4 -> 9 -> <nil>
$