Add Sleep Sort Algorithm in R

[Siddhram]

This PR introduces Sleep Sort, a playful and educational sorting algorithm implemented in R.
Sleep Sort launches one task per element, sleeps for a duration proportional to the element's value, and outputs the value when the task completes. The values appear in ascending order based on their "wake-up" times.

Overview

• Algorithm Type: Demonstrative / Novelty sorting algorithm
• Target Data: Numeric vectors (supports negative values via offsetting)
• Execution: Uses parallel tasks via a PSOCK cluster from the parallel package
• Windows Compatible: Handles timing via file modification times to capture completion order
• Notes: Intended for educational purposes; not recommended for production due to its reliance on sleep delays

Features

• Sorts numeric vectors using timed task execution
• Supports negative numbers by shifting all values to non-negative sleep times
• Adjustable scale parameter to control sleep duration
• Parallel execution with configurable number of workers
• Automatic fallback to base R sort() if parallel execution fails

Complexity

• Time Complexity (TC): O(n) in terms of task scheduling, but overall runtime depends on the largest element × scale
• Space Complexity (SC): O(n) for temporary files and parallel tasks

[Copilot]

Pull Request Overview

This PR adds a Sleep Sort implementation to the repository, a novelty sorting algorithm that sorts elements by launching parallel tasks that sleep for durations proportional to each element's value. The algorithm uses R's parallel package with PSOCK clusters and file modification times to capture completion order.

Key Changes:

• Implements sleep sort with support for negative numbers via offsetting
• Uses parallel execution with configurable workers and adjustable sleep scaling
• Includes fallback to base sort() if parallel execution fails

[Copilot]

The random directory name generation could produce collisions if multiple instances run simultaneously. Use tempfile() instead, which guarantees unique temporary paths: outdir <- tempfile(pattern = 'sleep_sort_').

Suggested change

	outdir <- file.path(tempdir(), paste0("sleep_sort_", as.integer(runif(1) * 1e9)))
	outdir <- tempfile(pattern = "sleep_sort_")

[Copilot]

The temporary directory is never cleaned up after function execution. Add on.exit(unlink(outdir, recursive = TRUE), add = TRUE) after line 39 to ensure cleanup even if an error occurs.

Suggested change

	dir.create(outdir, recursive = TRUE, showWarnings = FALSE)
	dir.create(outdir, recursive = TRUE, showWarnings = FALSE)
	on.exit(unlink(outdir, recursive = TRUE), add = TRUE)

[Copilot]

The magic number 50 for retry attempts lacks context. Extract this as a named constant (e.g., max_retries <- 50) to clarify its purpose and make it easier to adjust.

Suggested change

	while (tries < 50 && length(files) != n) {
	max_retries <- 50
	while (tries < max_retries && length(files) != n) {

[siriak]

Please address comments