Add problem 3002: Maximum Size of a Set After Removals

Author: EFanZh

src/lib.rs

@@ -2043,6 +2043,7 @@ pub mod problem_2996_smallest_missing_integer_greater_than_sequential_prefix_sum
 pub mod problem_2997_minimum_number_of_operations_to_make_array_xor_equal_to_k;
 pub mod problem_3000_maximum_area_of_longest_diagonal_rectangle;
 pub mod problem_3001_minimum_moves_to_capture_the_queen;
+pub mod problem_3005_count_elements_with_maximum_frequency;
 
 #[cfg(test)]
 mod test_utilities;

src/problem_3005_count_elements_with_maximum_frequency/iterative.rs

@@ -0,0 +1,48 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+use std::cmp::Ordering;
+
+impl Solution {
+    pub fn max_frequency_elements(nums: Vec<i32>) -> i32 {
+        let mut max_frequency = 0;
+        let mut max_frequency_sum = 0;
+        let mut frequencies = [0_u8; 100];
+
+        for num in nums {
+            let frequency = &mut frequencies[num.cast_unsigned() as usize - 1];
+
+            *frequency += 1;
+
+            let frequency = u32::from(*frequency);
+
+            match frequency.cmp(&max_frequency) {
+                Ordering::Less => {}
+                Ordering::Equal => max_frequency_sum += max_frequency,
+                Ordering::Greater => {
+                    max_frequency = frequency;
+                    max_frequency_sum = max_frequency;
+                }
+            }
+        }
+
+        max_frequency_sum.cast_signed()
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn max_frequency_elements(nums: Vec<i32>) -> i32 {
+        Self::max_frequency_elements(nums)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_3005_count_elements_with_maximum_frequency/mod.rs

@@ -0,0 +1,18 @@
+pub mod iterative;
+
+pub trait Solution {
+    fn max_frequency_elements(nums: Vec<i32>) -> i32;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [(&[1, 2, 2, 3, 1, 4] as &[_], 4), (&[1, 2, 3, 4, 5], 5)];
+
+        for (nums, expected) in test_cases {
+            assert_eq!(S::max_frequency_elements(nums.to_vec()), expected);
+        }
+    }
+}