Add problem 2405: Optimal Partition of String

src/lib.rs

@@ -1791,6 +1791,7 @@ pub mod problem_2400_number_of_ways_to_reach_a_position_after_exactly_k_steps;
 pub mod problem_2401_longest_nice_subarray;
 pub mod problem_2402_meeting_rooms_iii;
 pub mod problem_2404_most_frequent_even_element;
+pub mod problem_2405_optimal_partition_of_string;
 
 #[cfg(test)]
 mod test_utilities;

src/problem_2405_optimal_partition_of_string/bit_manipulation.rs

@@ -0,0 +1,47 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    pub fn partition_string(s: String) -> i32 {
+        let mut iter = s.bytes();
+        let mut c = iter.next().unwrap();
+        let mut used = 0_u32;
+        let mut result = 1;
+
+        loop {
+            let probe = 1 << (c - b'a');
+
+            if used & probe == 0 {
+                used |= probe;
+            } else {
+                result += 1;
+                used = probe;
+            }
+
+            if let Some(next) = iter.next() {
+                c = next;
+            } else {
+                break;
+            }
+        }
+
+        result
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn partition_string(s: String) -> i32 {
+        Self::partition_string(s)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_2405_optimal_partition_of_string/mod.rs

@@ -0,0 +1,18 @@
+pub mod bit_manipulation;
+
+pub trait Solution {
+    fn partition_string(s: String) -> i32;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [("abacaba", 4), ("ssssss", 6)];
+
+        for (s, expected) in test_cases {
+            assert_eq!(S::partition_string(s.to_string()), expected);
+        }
+    }
+}