Add problem 3170: Lexicographically Minimum String After Removing Stars

Author: EFanZh

src/lib.rs

@@ -2119,6 +2119,7 @@ pub mod problem_3163_string_compression_iii;
 pub mod problem_3164_find_the_number_of_good_pairs_ii;
 pub mod problem_3168_minimum_number_of_chairs_in_a_waiting_room;
 pub mod problem_3169_count_days_without_meetings;
+pub mod problem_3170_lexicographically_minimum_string_after_removing_stars;
 pub mod problem_3350_adjacent_increasing_subarrays_detection_ii;
 
 #[cfg(test)]

src/problem_3170_lexicographically_minimum_string_after_removing_stars/greedy.rs

@@ -0,0 +1,42 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    pub fn clear_stars(s: String) -> String {
+        let mut indices = [const { Vec::new() }; 26];
+        let mut s = s.into_bytes();
+
+        for i in 0..s.len() {
+            let c = s[i];
+
+            if let Some(indices) = indices.get_mut(usize::from(c).wrapping_sub(usize::from(b'a'))) {
+                indices.push(i as u32);
+            } else {
+                let index = indices.iter_mut().find_map(Vec::pop).unwrap();
+
+                s[index as usize] = b'*';
+            }
+        }
+
+        s.retain(|&c| c != b'*');
+
+        String::from_utf8(s).unwrap()
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn clear_stars(s: String) -> String {
+        Self::clear_stars(s)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_3170_lexicographically_minimum_string_after_removing_stars/mod.rs

@@ -0,0 +1,18 @@
+pub mod greedy;
+
+pub trait Solution {
+    fn clear_stars(s: String) -> String;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [("aaba*", "aab"), ("abc", "abc")];
+
+        for (s, expected) in test_cases {
+            assert_eq!(S::clear_stars(s.to_string()), expected);
+        }
+    }
+}