Add problem 2215: Find the Difference of Two Arrays

src/lib.rs

@@ -1481,6 +1481,7 @@ pub mod problem_2186_minimum_number_of_steps_to_make_two_strings_anagram_ii;
 pub mod problem_2190_most_frequent_number_following_key_in_an_array;
 pub mod problem_2194_cells_in_a_range_on_an_excel_sheet;
 pub mod problem_2206_divide_array_into_equal_pairs;
+pub mod problem_2215_find_the_difference_of_two_arrays;
 
 #[cfg(test)]
 mod test_utilities;

src/problem_2215_find_the_difference_of_two_arrays/hash_set.rs

@@ -0,0 +1,33 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+use std::collections::HashSet;
+
+impl Solution {
+    pub fn find_difference(nums1: Vec<i32>, nums2: Vec<i32>) -> Vec<Vec<i32>> {
+        let nums1 = nums1.into_iter().collect::<HashSet<_>>();
+        let nums2 = nums2.into_iter().collect::<HashSet<_>>();
+
+        vec![
+            nums1.difference(&nums2).copied().collect(),
+            nums2.difference(&nums1).copied().collect(),
+        ]
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn find_difference(nums1: Vec<i32>, nums2: Vec<i32>) -> Vec<Vec<i32>> {
+        Self::find_difference(nums1, nums2)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_2215_find_the_difference_of_two_arrays/mod.rs

@@ -0,0 +1,30 @@
+pub mod hash_set;
+
+pub trait Solution {
+    fn find_difference(nums1: Vec<i32>, nums2: Vec<i32>) -> Vec<Vec<i32>>;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [
+            (
+                (&[1, 2, 3] as &[_], &[2, 4, 6] as &[_]),
+                [&[1, 3] as &[_], &[4, 6] as &[_]],
+            ),
+            ((&[1, 2, 3, 3], &[1, 1, 2, 2]), [&[3] as &[_], &[] as &[_]]),
+        ];
+
+        for ((nums1, nums2), expected) in test_cases {
+            let mut result = S::find_difference(nums1.to_vec(), nums2.to_vec());
+
+            for value in &mut result {
+                value.sort_unstable();
+            }
+
+            assert_eq!(result, expected.map(Vec::from),);
+        }
+    }
+}