Add problem 1837: Sum of Digits in Base K

src/lib.rs

@@ -1414,6 +1414,7 @@ pub mod problem_1824_minimum_sideway_jumps;
 pub mod problem_1827_minimum_operations_to_make_the_array_increasing;
 pub mod problem_1832_check_if_the_sentence_is_pangram;
 pub mod problem_1833_maximum_ice_cream_bars;
+pub mod problem_1837_sum_of_digits_in_base_k;
 
 #[cfg(test)]
 mod test_utilities;

src/problem_1837_sum_of_digits_in_base_k/iterative.rs

@@ -0,0 +1,36 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+use std::num::NonZeroU8;
+
+impl Solution {
+    pub fn sum_base(n: i32, k: i32) -> i32 {
+        let mut n = n as u8;
+        let k = NonZeroU8::new(k as _).unwrap();
+        let mut result = 0;
+
+        while n != 0 {
+            result += n % k;
+            n = n / k;
+        }
+
+        i32::from(result)
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn sum_base(n: i32, k: i32) -> i32 {
+        Self::sum_base(n, k)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_1837_sum_of_digits_in_base_k/mod.rs

@@ -0,0 +1,18 @@
+pub mod iterative;
+
+pub trait Solution {
+    fn sum_base(n: i32, k: i32) -> i32;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [((34, 6), 9), ((10, 10), 1)];
+
+        for ((n, k), expected) in test_cases {
+            assert_eq!(S::sum_base(n, k), expected);
+        }
+    }
+}