20250325 finished.

src/problem/mod.rs

@@ -558,3 +558,5 @@ mod p2643_row_with_maximum_ones;
 mod p2116_check_if_a_parentheses_string_can_be_valid;
 
 mod p2255_count_prefixes_of_a_given_string;
+
+mod p2711_difference_of_number_of_distinct_values_on_diagonals;

src/problem/p2711_difference_of_number_of_distinct_values_on_diagonals.rs

@@ -0,0 +1,95 @@
+/**
+ * [2711] Difference of Number of Distinct Values on Diagonals
+ */
+pub struct Solution {}
+
+// submission codes start here
+use std::collections::HashMap;
+use std::collections::HashSet;
+
+impl Solution {
+    pub fn difference_of_distinct_values(grid: Vec<Vec<i32>>) -> Vec<Vec<i32>> {
+        let m = grid.len();
+        let n = grid[0].len();
+        let mut result = vec![vec![0; n]; m];
+
+        Self::iterate_diagonal(&grid, &mut result, (0..m).rev().map(|i| (i, 0)));
+        Self::iterate_diagonal(&grid, &mut result, (0..n).rev().map(|i| (0, i)));
+
+        result
+    }
+
+    fn iterate_diagonal<T>(grid: &Vec<Vec<i32>>, result: &mut Vec<Vec<i32>>, iter: T)
+    where
+        T: Iterator<Item = (usize, usize)>,
+    {
+        let m = grid.len();
+        let n = grid[0].len();
+        let max_length = m.min(n);
+
+        let mut length = 1;
+        for (i, j) in iter {
+            let mut left_set = HashSet::with_capacity(length);
+            // 右下对角线因为涉及到添加和删除
+            // 使用哈希表存储对应数字的出现次数
+            let mut right_set = HashMap::with_capacity(length);
+
+            // 首先遍历右下
+            let (mut x, mut y) = (i + 1, j + 1);
+
+            for _ in 1..length {
+                let entry = right_set.entry(grid[x][y]).or_insert(0);
+                *entry += 1;
+
+                x += 1;
+                y += 1;
+            }
+
+            // 然后开始遍历
+            let (mut x, mut y) = (i, j);
+
+            for k in 0..length {
+                // 删除右下对角线
+                if k != 0 {
+                    let entry = right_set.get_mut(&grid[x][y]).unwrap();
+                    *entry -= 1;
+                    if *entry == 0 {
+                        right_set.remove(&grid[x][y]);
+                    }
+                }
+
+                result[x][y] = left_set.len().abs_diff(right_set.len()) as i32;
+
+                // 插入左上对角线
+                left_set.insert(grid[x][y]);
+                x += 1;
+                y += 1;
+            }
+
+            length = max_length.min(length + 1);
+        }
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_2711() {
+        assert_eq!(
+            vec![vec![1, 1, 0], vec![1, 0, 1], vec![0, 1, 1]],
+            Solution::difference_of_distinct_values(vec![
+                vec![1, 2, 3],
+                vec![3, 1, 5],
+                vec![3, 2, 1]
+            ])
+        );
+        assert_eq!(
+            vec![vec![0]],
+            Solution::difference_of_distinct_values(vec![vec![1]])
+        );
+    }
+}