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Problem

Submissions

Delete Alternate Nodes

Contributed by

Pankaj Sharma

Last Updated: 23 Feb, 2023

Easy

0/40

Avg time to solve 20 mins

Success Rate 80 %

20 upvotes

Problem Statement

Given a Singly Linked List of integers, delete all the alternate nodes in the list.

Example:

List: 10 -> 20 -> 30 -> 40 -> 50 -> 60 -> null
Alternate nodes will be:  20, 40, and 60.

Hence after deleting, the list will be:
Output: 10 -> 30 -> 50 -> null

Note :

The head of the list will remain the same. Don't need to print or return anything.

Detailed explanation ( Input/output format, Notes, Images )

Input format :

The first and the only line of input will contain the elements of the Singly Linked List separated by a single space and terminated by -1.

Output Format :

The only line of output will contain the updated list elements.

Input Constraints:

1 <= N <= 10 ^ 6.
Where N is the size of the Singly Linked List

Time Limit: 1 sec

Sample Input 1:

1 2 3 4 5 -1

Sample Output 1:

1 3 5

Explanation of Sample Input 1:

2, 4 are alternate nodes so we need to delete them

Sample Input 2:

10 20 30 40 50 60 70 -1

Sample Output 2:

10 30 50 70

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