Add problem 1717: Maximum Score From Removing Substrings

src/lib.rs

@@ -1385,6 +1385,7 @@ pub mod problem_1710_maximum_units_on_a_truck;
 pub mod problem_1711_count_good_meals;
 pub mod problem_1712_ways_to_split_array_into_three_subarrays;
 pub mod problem_1716_calculate_money_in_leetcode_bank;
+pub mod problem_1717_maximum_score_from_removing_substrings;
 pub mod problem_1720_decode_xored_array;
 pub mod problem_1721_swapping_nodes_in_a_linked_list;
 pub mod problem_1725_number_of_rectangles_that_can_form_the_largest_square;

src/problem_1717_maximum_score_from_removing_substrings/greedy.rs

@@ -0,0 +1,49 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    pub fn maximum_gain(s: String, x: i32, y: i32) -> i32 {
+        let (first, second, x, y) = if y < x { (b'a', b'b', x, y) } else { (b'b', b'a', y, x) };
+        let mut num_first = 0;
+        let mut num_second = 0;
+        let mut result = 0;
+
+        for c in s.into_bytes() {
+            if c == first {
+                num_first += 1;
+            } else if c == second {
+                if num_first == 0 {
+                    num_second += 1;
+                } else {
+                    num_first -= 1;
+                    result += x;
+                }
+            } else {
+                result += y * num_second.min(num_first);
+                num_first = 0;
+                num_second = 0;
+            }
+        }
+
+        result += y * num_second.min(num_first);
+
+        result
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn maximum_gain(s: String, x: i32, y: i32) -> i32 {
+        Self::maximum_gain(s, x, y)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_1717_maximum_score_from_removing_substrings/greedy_2.rs

@@ -0,0 +1,56 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    fn check<const A: u8, const B: u8>(s: &str, x: i32, y: i32) -> i32 {
+        let mut num_first = 0;
+        let mut num_second = 0;
+        let mut result = 0;
+
+        for c in s.bytes() {
+            if c == A {
+                num_first += 1;
+            } else if c == B {
+                if num_first == 0 {
+                    num_second += 1;
+                } else {
+                    num_first -= 1;
+                    result += x;
+                }
+            } else {
+                result += y * num_second.min(num_first);
+                num_first = 0;
+                num_second = 0;
+            }
+        }
+
+        result += y * num_second.min(num_first);
+
+        result
+    }
+
+    pub fn maximum_gain(s: String, x: i32, y: i32) -> i32 {
+        if y < x {
+            Self::check::<b'a', b'b'>(&s, x, y)
+        } else {
+            Self::check::<b'b', b'a'>(&s, y, x)
+        }
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn maximum_gain(s: String, x: i32, y: i32) -> i32 {
+        Self::maximum_gain(s, x, y)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_1717_maximum_score_from_removing_substrings/mod.rs

@@ -0,0 +1,19 @@
+pub mod greedy;
+pub mod greedy_2;
+
+pub trait Solution {
+    fn maximum_gain(s: String, x: i32, y: i32) -> i32;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [(("cdbcbbaaabab", 4, 5), 19), (("aabbaaxybbaabb", 5, 4), 20)];
+
+        for ((s, x, y), expected) in test_cases {
+            assert_eq!(S::maximum_gain(s.to_string(), x, y), expected);
+        }
+    }
+}