Prevent is_circular function from infinite loop #179
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Transform the is_circular function by shifting from a single pointer approach to employing slow and fast pointers. The single pointer method falls short in detecting loops that occur mid-list without additional storage. Utilizing slow and fast pointers overcomes this limitation, enabling the detection of mid-list loops. Although this approach introduces a slight increase in conditional checks, it remains a superior method for loop detection without the need for extra storage.
jserv
requested changes
Mar 28, 2024
jserv
reviewed
Mar 28, 2024
wilson20010327
changed the title
To follow the coding style, remove the usless parentheses.
wilson20010327
force-pushed
the
fix_check_q_circular
branch
from
e546fec to
bc0d83a
Compare
|
Thank @wilson20010327 for contributing! |
Huadesuwa
pushed a commit
to Huadesuwa/lab0-c
that referenced
this pull request
Mar 21, 2025
This commit refines the is_circular() to use slow and fast pointers instead of a single pointer iteration. The original approach struggled to detect mid-list loops without extra storage. The new method effectively identifies such loops, albeit with a minor increase in conditional checks, but without requiring additional storage.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Original function will face infinite loop when there is a mid-list loop in queue. Transform the is_circular function by shifting from a single pointer approach to employing slow and fast pointers. The single pointer method falls short in detecting loops that occur mid-list without additional storage. Utilizing slow and fast pointers overcomes this limitation, enabling the detection of mid-list loops. Although this approach introduces a slight increase in conditional checks, it remains a superior method for loop detection without the need for extra storage.