20240616 Finished

src/problem/mod.rs

@@ -150,3 +150,4 @@ mod p124_binary_tree_maximum_path_sum;
 mod p173_binary_search_tree_iterator;
 mod p222_count_complete_tree_nodes;
 mod p199_binary_tree_right_side_view;
+mod p637_average_of_levels_in_binary_tree;

src/problem/p637_average_of_levels_in_binary_tree.rs

@@ -0,0 +1,75 @@
+/**
+ * [637] Average of Levels in Binary Tree
+ */
+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 average_of_levels(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<f64> {
+        let mut result = vec![];
+
+        let mut queue = VecDeque::new();
+
+        if let Some(root) = root {
+            queue.push_back(root);
+        }
+
+        while !queue.is_empty() {
+            let length = queue.len();
+
+            let mut sum = 0f64;
+            for _ in 0..length {
+                let node = queue.pop_front().unwrap();
+
+                sum += node.borrow().val as f64;
+
+                if let Some(left) = &node.borrow().left {
+                    queue.push_back(Rc::clone(left));
+                };
+
+                if let Some(right) = &node.borrow().right {
+                    queue.push_back(Rc::clone(right));
+                };
+            }
+
+            result.push(sum / length as f64);
+        }
+
+        result
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_637() {
+    }
+}