Add problem 1945: Sum of Digits of String After Convert

src/lib.rs

@@ -1473,6 +1473,7 @@ pub mod problem_1926_nearest_exit_from_entrance_in_maze;
 pub mod problem_1929_concatenation_of_array;
 pub mod problem_1935_maximum_number_of_words_you_can_type;
 pub mod problem_1941_check_if_all_characters_have_equal_number_of_occurrences;
+pub mod problem_1945_sum_of_digits_of_string_after_convert;
 
 #[cfg(test)]
 mod test_utilities;

src/problem_1945_sum_of_digits_of_string_after_convert/iterative.rs

@@ -0,0 +1,49 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    pub fn get_lucky(s: String, k: i32) -> i32 {
+        let k = k as u32;
+        let mut value = 0;
+
+        // Convert and transform.
+
+        for c in s.into_bytes() {
+            let c = c - (b'a' - 1);
+
+            value += u16::from(c / 10 + c % 10);
+        }
+
+        // Transform.
+
+        for _ in 1..k {
+            let mut temp = 0;
+
+            while value != 0 {
+                temp += value % 10;
+                value /= 10;
+            }
+
+            value = temp;
+        }
+
+        i32::from(value)
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn get_lucky(s: String, k: i32) -> i32 {
+        Self::get_lucky(s, k)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_1945_sum_of_digits_of_string_after_convert/mod.rs

@@ -0,0 +1,18 @@
+pub mod iterative;
+
+pub trait Solution {
+    fn get_lucky(s: String, k: i32) -> i32;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [(("iiii", 1), 36), (("leetcode", 2), 6), (("zbax", 2), 8)];
+
+        for ((s, k), expected) in test_cases {
+            assert_eq!(S::get_lucky(s.to_string(), k), expected);
+        }
+    }
+}