From 3738fea7bbc090e8fda4e91ff5c7a57073757643 Mon Sep 17 00:00:00 2001
From: EFanZh <efanzh@gmail.com>
Date: Sun, 25 Feb 2024 13:10:54 +0800
Subject: [PATCH] Add problem 2149: Rearrange Array Elements by Sign

---
 src/lib.rs                                    |  1 +
 .../iterative.rs                              | 40 +++++++++++++++++++
 .../mod.rs                                    | 21 ++++++++++
 3 files changed, 62 insertions(+)
 create mode 100644 src/problem_2149_rearrange_array_elements_by_sign/iterative.rs
 create mode 100644 src/problem_2149_rearrange_array_elements_by_sign/mod.rs

diff --git a/src/lib.rs b/src/lib.rs
index 2a49cc9b..e597a903 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1459,6 +1459,7 @@ pub mod problem_2138_divide_a_string_into_groups_of_size_k;
 pub mod problem_2140_solving_questions_with_brainpower;
 pub mod problem_2144_minimum_cost_of_buying_candies_with_discount;
 pub mod problem_2148_count_elements_with_strictly_smaller_and_greater_elements;
+pub mod problem_2149_rearrange_array_elements_by_sign;
 
 #[cfg(test)]
 mod test_utilities;
diff --git a/src/problem_2149_rearrange_array_elements_by_sign/iterative.rs b/src/problem_2149_rearrange_array_elements_by_sign/iterative.rs
new file mode 100644
index 00000000..479ca7fa
--- /dev/null
+++ b/src/problem_2149_rearrange_array_elements_by_sign/iterative.rs
@@ -0,0 +1,40 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    pub fn rearrange_array(nums: Vec<i32>) -> Vec<i32> {
+        let mut result = vec![0; nums.len()];
+        let mut positive_index = 0;
+        let mut negative_index = 1;
+
+        for num in nums {
+            let index = if num < 0 {
+                &mut negative_index
+            } else {
+                &mut positive_index
+            };
+
+            result[*index] = num;
+            *index += 2;
+        }
+
+        result
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn rearrange_array(nums: Vec<i32>) -> Vec<i32> {
+        Self::rearrange_array(nums)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}
diff --git a/src/problem_2149_rearrange_array_elements_by_sign/mod.rs b/src/problem_2149_rearrange_array_elements_by_sign/mod.rs
new file mode 100644
index 00000000..c2db40ce
--- /dev/null
+++ b/src/problem_2149_rearrange_array_elements_by_sign/mod.rs
@@ -0,0 +1,21 @@
+pub mod iterative;
+
+pub trait Solution {
+    fn rearrange_array(nums: Vec<i32>) -> Vec<i32>;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [
+            (&[3, 1, -2, -5, 2, -4] as &[_], &[3, -2, 1, -5, 2, -4] as &[_]),
+            (&[-1, 1], &[1, -1]),
+        ];
+
+        for (nums, expected) in test_cases {
+            assert_eq!(S::rearrange_array(nums.to_vec()), expected);
+        }
+    }
+}