20240226 Finished

src/problem/mod.rs

@@ -55,3 +55,4 @@ mod p106_construct_binary_tree_from_inorder_and_postorder_traversal;
 mod p235_lowest_common_ancestor_of_a_binary_search_tree;
 mod p2583_kth_largest_sum_in_a_binary_tree;
 mod p2476_closest_nodes_queries_in_a_binary_search_tree;
+mod p938_range_sum_of_bst;

src/problem/p938_range_sum_of_bst.rs

@@ -0,0 +1,79 @@
+/**
+ * [938] Range Sum of BST
+ */
+pub struct Solution {}
+
+use crate::util::tree::{TreeNode, to_tree};
+
+// submission codes start here
+
+// Definition for a binary tree node.
+// #[derive(Debug, PartialEq, Eq)]
+// pub struct TreeNode {
+//   pub val: i32,
+//   pub left: Option<Rc<RefCell<TreeNode>>>,
+//   pub right: Option<Rc<RefCell<TreeNode>>>,
+// }
+//
+// impl TreeNode {
+//   #[inline]
+//   pub fn new(val: i32) -> Self {
+//     TreeNode {
+//       val,
+//       left: None,
+//       right: None
+//     }
+//   }
+// }
+use std::rc::Rc;
+use std::cell::RefCell;
+use std::collections::VecDeque;
+impl Solution {
+    pub fn range_sum_bst(root: Option<Rc<RefCell<TreeNode>>>, low: i32, high: i32) -> i32 {
+        let root = if let Some(r) = root {
+            r
+        } else {
+            return 0;
+        };
+
+        let mut sum = 0;
+
+        let mut deque = VecDeque::new();
+        deque.push_back(root);
+
+        while !deque.is_empty() {
+            let node = deque.pop_front().unwrap();
+
+            if node.borrow().val >= low && node.borrow().val <= high {
+                sum += node.borrow().val;
+            }
+
+            if node.borrow().val > low {
+                if let Some(left) = &node.borrow().left {
+                    deque.push_back(Rc::clone(left));
+                }
+            }
+
+            if node.borrow().val < high {
+                if let Some(right) = &node.borrow().right {
+                    deque.push_back(Rc::clone(right));
+                }
+            }
+        }
+
+        sum
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_938() {
+        assert_eq!(Solution::range_sum_bst(
+            to_tree(vec![Some(10), Some(5), Some(15), Some(3), Some(7), None, Some(18)]), 7, 15), 32);
+    }
+}