Add problem 2160: Minimum Sum of Four Digit Number After Splitting Di…

…gits

src/lib.rs

@@ -1465,6 +1465,7 @@ pub mod problem_2149_rearrange_array_elements_by_sign;
 pub mod problem_2150_find_all_lonely_numbers_in_the_array;
 pub mod problem_2154_keep_multiplying_found_values_by_two;
 pub mod problem_2155_all_divisions_with_the_highest_score_of_a_binary_array;
+pub mod problem_2160_minimum_sum_of_four_digit_number_after_splitting_digits;
 
 #[cfg(test)]
 mod test_utilities;

src/problem_2160_minimum_sum_of_four_digit_number_after_splitting_digits/mathematical.rs

@@ -0,0 +1,43 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl Solution {
+    pub fn minimum_sum(num: i32) -> i32 {
+        let mut num = num as u16;
+        let a = (num % 10) as u8;
+
+        num /= 10;
+
+        let b = (num % 10) as u8;
+
+        num /= 10;
+
+        let c = (num % 10) as u8;
+        let d = (num / 10) as u8;
+
+        let mut digits = [a, b, c, d];
+
+        digits.sort_unstable();
+
+        let [a, b, c, d] = digits;
+
+        i32::from((a + b) * 10 + c + d)
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn minimum_sum(num: i32) -> i32 {
+        Self::minimum_sum(num)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_2160_minimum_sum_of_four_digit_number_after_splitting_digits/mod.rs

@@ -0,0 +1,18 @@
+pub mod mathematical;
+
+pub trait Solution {
+    fn minimum_sum(num: i32) -> i32;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [(2932, 52), (4009, 13)];
+
+        for (num, expected) in test_cases {
+            assert_eq!(S::minimum_sum(num), expected);
+        }
+    }
+}