20240131 Finished

src/problem/mod.rs

@@ -33,3 +33,4 @@ mod p2861_maximum_number_of_alloys;
 mod p365_water_and_jug_problem;
 mod p514_freedom_trail;
 mod p2808_minimum_seconds_to_equalize_a_circular_array;
+mod p2670_find_the_distinct_difference_array;

src/problem/p2670_find_the_distinct_difference_array.rs

@@ -0,0 +1,52 @@
+/**
+ * [2670] Find the Distinct Difference Array
+ */
+pub struct Solution {}
+
+
+// submission codes start here
+
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn distinct_difference_array(nums: Vec<i32>) -> Vec<i32> {
+        let mut right = HashMap::new();
+
+        for i in &nums {
+            let entry = right.entry(*i).or_insert(0);
+            *entry += 1;
+        }
+
+        let mut result = Vec::with_capacity(nums.len());
+        let mut left = HashMap::new();
+
+        for i in &nums {
+            let left_entry = left.entry(*i).or_insert(0);
+            *left_entry += 1;
+
+            let right_entry = right.get_mut(i).unwrap();
+            *right_entry -= 1;
+
+            if *right_entry == 0 {
+                right.remove(i);
+            }
+
+            result.push(left.len() as i32 - right.len() as i32);
+        }
+
+        result
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_2670() {
+        assert_eq!(Solution::distinct_difference_array(vec![1, 2, 3, 4, 5]),
+                   vec![-3, -1, 1, 3, 5]);
+    }
+}