From cb0cd5a9f5053147ddc8bfd783d89eeed9170789 Mon Sep 17 00:00:00 2001
From: Vishal Pankaj Chandratreya <19171016+tfpf@users.noreply.github.com>
Date: Sun, 5 May 2024 00:41:55 +0530
Subject: [PATCH 1/3] Removed the multithreading helper of
 `is_small_prime_small_test`.

---
 src/utils.rs | 26 +++++++++-----------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/src/utils.rs b/src/utils.rs
index 263679e..d63de38 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -262,33 +262,25 @@ mod tests {
         reader.lines().map(|line| line.unwrap())
     }
 
-    /// Convenience to count the number of prime numbers in a given range using
-    /// multiple threads.
-    ///
-    /// * `lower` - First number of the range (inclusive).
-    /// * `upper` - Last number of the range (exclusive).
-    /// * `pieces` - Number of threads to use.
-    ///
-    /// -> Number of primes numbers in the range.
-    fn primes(lower: i64, upper: i64, pieces: i64) -> usize {
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn is_prime_small_test() {
+        // Break the range into equal sub-ranges, and count the number of
+        // primes in each sub-range in a separate thread.
+        let (lower, upper, pieces) = (0, 3i64.pow(20), 20);
         let search_space = upper - lower;
         let search_space = search_space / pieces + if search_space % pieces == 0 { 0 } else { 1 };
-        (lower..upper)
+        let num_of_primes = (lower..upper)
             .step_by(search_space as usize)
             .map(|lower| {
                 let upper = std::cmp::min(lower + search_space, upper);
+                println!("{} {}", upper, lower);
                 std::thread::spawn(move || (lower..upper).filter(|&num| utils::is_prime(num)).count())
             })
             .collect::<Vec<_>>()
             .into_iter()
             .map(|worker| worker.join().unwrap())
-            .sum()
-    }
-
-    #[cfg(target_pointer_width = "64")]
-    #[test]
-    fn is_prime_small_test() {
-        let num_of_primes = primes(0, 3i64.pow(20), 3);
+            .sum::<usize>();
         assert_eq!(num_of_primes, 166677978);
     }
 

From 92ea3acd5867f6b0d2bc156ae296987c3efa16ce Mon Sep 17 00:00:00 2001
From: Vishal Pankaj Chandratreya <19171016+tfpf@users.noreply.github.com>
Date: Sun, 5 May 2024 00:43:23 +0530
Subject: [PATCH 2/3] Removed debug print.

---
 src/utils.rs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/utils.rs b/src/utils.rs
index d63de38..b7a061d 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -274,7 +274,6 @@ mod tests {
             .step_by(search_space as usize)
             .map(|lower| {
                 let upper = std::cmp::min(lower + search_space, upper);
-                println!("{} {}", upper, lower);
                 std::thread::spawn(move || (lower..upper).filter(|&num| utils::is_prime(num)).count())
             })
             .collect::<Vec<_>>()

From eed0c2984d5dcddbb811b1828ff63120f7ce83db Mon Sep 17 00:00:00 2001
From: Vishal Pankaj Chandratreya <19171016+tfpf@users.noreply.github.com>
Date: Sun, 5 May 2024 00:44:34 +0530
Subject: [PATCH 3/3] Reduced to 3 threads.

More suitable for GitHub Actions runner.
---
 src/utils.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/utils.rs b/src/utils.rs
index b7a061d..ba2245b 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -267,7 +267,7 @@ mod tests {
     fn is_prime_small_test() {
         // Break the range into equal sub-ranges, and count the number of
         // primes in each sub-range in a separate thread.
-        let (lower, upper, pieces) = (0, 3i64.pow(20), 20);
+        let (lower, upper, pieces) = (0, 3i64.pow(20), 3);
         let search_space = upper - lower;
         let search_space = search_space / pieces + if search_space % pieces == 0 { 0 } else { 1 };
         let num_of_primes = (lower..upper)