8-15-2020

Author: safrannn

src/_0938_range_sum_of_bst.rs

@@ -0,0 +1,29 @@
+struct Solution;
+use crate::util::*;
+use std::cell::RefCell;
+use std::rc::Rc;
+
+impl Solution {
+    pub fn range_sum_bst(root: Option<Rc<RefCell<TreeNode>>>, l: i32, r: i32) -> i32 {
+        let mut sum: i32 = 0;
+        Self::traverse(&root, l, r, &mut sum);
+        sum
+    }
+
+    fn traverse(root: &Option<Rc<RefCell<TreeNode>>>, l: i32, r: i32, sum: &mut i32) {
+        if let Some(node) = root {
+            let h_value: i32 = node.borrow().val;
+            if h_value >= l && h_value <= r {
+                *sum += h_value;
+            }
+            Self::traverse(&node.borrow().left, l, r, sum);
+            Self::traverse(&node.borrow().right, l, r, sum);
+        }
+    }
+}
+
+#[test]
+fn test() {
+    let root = tree!(10, tree!(5, tree!(3), tree!(7)), tree!(15, None, tree!(18)));
+    assert_eq!(Solution::range_sum_bst(root, 7, 15), 32);
+}

src/lib.rs

@@ -190,6 +190,8 @@ mod _0922_sort_array_by_parity_ii;
 //
 mod _0937_reorder_data_in_log_files;
 //
+mod _0938_range_sum_of_bst;
+//
 mod _0953_verifying_an_alien_dictionary;
 //
 mod _0977_squares_of_a_sorted_array;