LC 349. Intersection of Two Arrays (Rust Set)

README.md

@@ -220,6 +220,7 @@ Solutions to LeetCode problems. The first column links to the problem in LeetCod
 | [342. Power of Four][lc342]                                                                   | 🟢 Easy    | [![python](res/py.png)][lc342py] [![rust](res/rs.png)][lc342rs]                                       |
 | [345. Reverse Vowels of a String][lc345]                                                      | 🟢 Easy    | [![python](res/py.png)][lc345py]                                                                      |
 | [347. Top K Frequent Elements][lc347]                                                         | 🟠 Medium  | [![python](res/py.png)][lc347py] [![rust](res/rs.png)][lc347rs]                                       |
+| [349. Intersection of Two Arrays][lc349]                                                      | 🟢 Easy    | [![rust](res/rs.png)][lc349rs]                                                                        |
 | [352. Data Stream as Disjoint Intervals][lc352]                                               | 🔴 Hard    | [![python](res/py.png)][lc352py]                                                                      |
 | [355. Design Twitter][lc355]                                                                  | 🟠 Medium  | [![python](res/py.png)][lc355py]                                                                      |
 | [363. Max Sum of Rectangle No Larger Than K][lc363] ⚠️                                        | 🔴 Hard    | [![python](res/py.png)][lc363py]                                                                      |
@@ -1144,6 +1145,8 @@ Solutions to LeetCode problems. The first column links to the problem in LeetCod
 [lc347]: https://leetcode.com/problems/top-k-frequent-elements/
 [lc347py]: leetcode/top-k-frequent-elements.py
 [lc347rs]: leetcode/top-k-frequent-elements.rs
+[lc349]: https://leetcode.com/problems/intersection-of-two-arrays/
+[lc349rs]: leetcode/intersection-of-two-arrays.rs
 [lc352]: https://leetcode.com/problems/data-stream-as-disjoint-intervals/
 [lc352py]: leetcode/data-stream-as-disjoint-intervals.py
 [lc355]: https://leetcode.com/problems/design-twitter/

leetcode/intersection-of-two-arrays.rs

@@ -0,0 +1,63 @@
+// 349. Intersection of Two Arrays
+// 🟢 Easy
+//
+// https://leetcode.com/problems/intersection-of-two-arrays/
+//
+// Tags: Array - Hash Table - Two Pointers - Binary Search - Sorting
+
+use std::collections::HashSet;
+
+struct Solution;
+impl Solution {
+    /// Get a hashset from each input vector and compute their intersection, return the result as a
+    /// vector.
+    ///
+    /// Time complexity: O(m+n) - We will visit each element in both input vectors.
+    /// Space complexity: O(n) - To compute the intersection, at some point the iterators need to
+    /// store the elements in memory.
+    ///
+    /// Runtime 1 ms Beats 83.16%
+    /// Memory 2.17 MB Beats 74.74%
+    #[allow(dead_code)]
+    pub fn intersection(nums1: Vec<i32>, nums2: Vec<i32>) -> Vec<i32> {
+        nums1
+            .into_iter()
+            .collect::<HashSet<_>>()
+            .intersection(&nums2.into_iter().collect::<HashSet<_>>())
+            .map(|x| *x)
+            .collect::<Vec<_>>()
+    }
+}
+
+// Tests.
+fn main() {
+    let tests = [
+        (vec![1, 2, 2, 1], vec![2, 2], vec![2]),
+        (vec![4, 9, 5], vec![9, 4, 9, 8, 4], vec![4, 9]),
+    ];
+    println!("\n\x1b[92m» Running {} tests...\x1b[0m", tests.len());
+    let mut success = 0;
+    for (i, t) in tests.iter().enumerate() {
+        let res = Solution::intersection(t.0.clone(), t.1.clone());
+        if res == t.2 {
+            success += 1;
+            println!("\x1b[92m✔\x1b[95m Test {} passed!\x1b[0m", i);
+        } else {
+            println!(
+                "\x1b[31mx\x1b[95m Test {} failed expected: {:?} but got {:?}!!\x1b[0m",
+                i, t.2, res
+            );
+        }
+    }
+    println!();
+    if success == tests.len() {
+        println!("\x1b[30;42m✔ All tests passed!\x1b[0m")
+    } else if success == 0 {
+        println!("\x1b[31mx \x1b[41;37mAll tests failed!\x1b[0m")
+    } else {
+        println!(
+            "\x1b[31mx\x1b[95m {} tests failed!\x1b[0m",
+            tests.len() - success
+        )
+    }
+}