fix rust imports

neetcode-gh · neetcode-gh · commit e11a57fd6306 · 2026-02-21T22:05:32.000-08:00
diff --git a/articles/binary-search-tree-iterator.md b/articles/binary-search-tree-iterator.md
@@ -351,9 +351,6 @@ class BSTIterator {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 struct BSTIterator {
     arr: Vec<i32>,
     itr: usize,
@@ -721,9 +718,6 @@ class BSTIterator {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 struct BSTIterator {
     arr: Vec<i32>,
     itr: usize,
@@ -1070,9 +1064,6 @@ class BSTIterator {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 struct BSTIterator {
     stack: Vec<Rc<RefCell<TreeNode>>>,
 }
@@ -1396,9 +1387,6 @@ class BSTIterator {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 struct BSTIterator {
     cur: Option<Rc<RefCell<TreeNode>>>,
     stack: Vec<Rc<RefCell<TreeNode>>>,
diff --git a/articles/closest-binary-search-tree-value.md b/articles/closest-binary-search-tree-value.md
@@ -177,9 +177,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn closest_value(root: Option<Rc<RefCell<TreeNode>>>, target: f64) -> i32 {
         let mut nums = Vec::new();
@@ -440,9 +437,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn closest_value(root: Option<Rc<RefCell<TreeNode>>>, target: f64) -> i32 {
         let mut stack: Vec<Rc<RefCell<TreeNode>>> = Vec::new();
@@ -656,9 +650,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn closest_value(root: Option<Rc<RefCell<TreeNode>>>, target: f64) -> i32 {
         let mut curr = root;
diff --git a/articles/constrained-subsequence-sum.md b/articles/constrained-subsequence-sum.md
@@ -1401,8 +1401,6 @@ struct Heap<T> {
 ```
 
 ```rust
-use std::collections::BinaryHeap;
-
 impl Solution {
     pub fn constrained_subset_sum(nums: Vec<i32>, k: i32) -> i32 {
         let k = k as usize;
diff --git a/articles/construct-string-from-binary-tree.md b/articles/construct-string-from-binary-tree.md
@@ -318,8 +318,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
 impl Solution {
     pub fn tree2str(root: Option<Rc<RefCell<TreeNode>>>) -> String {
         match root {
diff --git a/articles/count-prefix-and-suffix-pairs-i.md b/articles/count-prefix-and-suffix-pairs-i.md
@@ -766,8 +766,6 @@ class Solution {
 ```
 
 ```rust
-use std::collections::HashMap;
-
 struct TrieNode {
     children: HashMap<(u8, u8), TrieNode>,
     count: i32,
diff --git a/articles/design-search-autocomplete-system.md b/articles/design-search-autocomplete-system.md
@@ -550,8 +550,6 @@ class AutocompleteSystem {
 ```
 
 ```rust
-use std::collections::HashMap;
-
 struct TrieNode {
     children: HashMap<char, usize>,
     sentences: HashMap<String, i32>,
@@ -1262,8 +1260,6 @@ class AutocompleteSystem {
 ```
 
 ```rust
-use std::collections::{BinaryHeap, HashMap};
-
 struct TrieNode {
     children: HashMap<char, usize>,
     sentences: HashMap<String, i32>,
diff --git a/articles/encode-n-ary-tree-to-binary-tree.md b/articles/encode-n-ary-tree-to-binary-tree.md
@@ -778,8 +778,6 @@ class Codec {
 // Uses TreeNode with Option<Rc<RefCell<TreeNode>>>
 // and a custom NaryNode for the N-ary tree.
 
-use std::collections::VecDeque;
-
 struct Codec;
 
 impl Codec {
diff --git a/articles/final-array-state-after-k-multiplication-operations-i.md b/articles/final-array-state-after-k-multiplication-operations-i.md
@@ -445,8 +445,6 @@ class Solution {
 ```
 
 ```rust
-use std::cmp::Reverse;
-
 impl Solution {
     pub fn get_final_state(nums: Vec<i32>, k: i32, multiplier: i32) -> Vec<i32> {
         let mut res = nums.clone();
diff --git a/articles/find-bottom-left-tree-value.md b/articles/find-bottom-left-tree-value.md
@@ -258,8 +258,6 @@ class Solution {
 
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
 impl Solution {
     pub fn find_bottom_left_value(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let mut q = VecDeque::new();
@@ -588,8 +586,6 @@ class Solution {
 
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
 impl Solution {
     pub fn find_bottom_left_value(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let mut max_depth = -1;
@@ -953,8 +949,6 @@ class Solution {
 
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
 impl Solution {
     pub fn find_bottom_left_value(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let mut res = root.as_ref().unwrap().borrow().val;
@@ -1408,8 +1402,6 @@ class Solution {
 
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
 impl Solution {
     pub fn find_bottom_left_value(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let mut res = root.as_ref().unwrap().borrow().val;
diff --git a/articles/find-duplicate-subtrees.md b/articles/find-duplicate-subtrees.md
@@ -419,9 +419,6 @@ class Solution {
 // comparison of tree node pointers, which doesn't directly
 // translate to Rust's Rc<RefCell<TreeNode>>. We use index-based
 // tracking instead.
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn find_duplicate_subtrees(
         root: Option<Rc<RefCell<TreeNode>>>,
@@ -750,9 +747,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn find_duplicate_subtrees(
         root: Option<Rc<RefCell<TreeNode>>>,
@@ -1090,9 +1084,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn find_duplicate_subtrees(
         root: Option<Rc<RefCell<TreeNode>>>,
diff --git a/articles/find-largest-value-in-each-tree-row.md b/articles/find-largest-value-in-each-tree-row.md
@@ -329,9 +329,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn largest_values(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<i32> {
         let mut res = Vec::new();
@@ -663,9 +660,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn largest_values(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<i32> {
         let mut res = Vec::new();
@@ -1026,9 +1020,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn largest_values(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<i32> {
         if root.is_none() { return vec![]; }
diff --git a/articles/find-leaves-of-binary-tree.md b/articles/find-leaves-of-binary-tree.md
@@ -435,9 +435,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn find_leaves(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<Vec<i32>> {
         let mut pairs: Vec<(i32, i32)> = Vec::new();
@@ -793,9 +790,6 @@ class Solution {
 ```
 
 ```rust
-use std::rc::Rc;
-use std::cell::RefCell;
-
 impl Solution {
     pub fn find_leaves(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<Vec<i32>> {
         let mut solution: Vec<Vec<i32>> = Vec::new();
diff --git a/articles/find-median-in-a-data-stream.md b/articles/find-median-in-a-data-stream.md
@@ -621,8 +621,6 @@ class MedianFinder {
 ```
 
 ```rust
-use std::cmp::Reverse;
-
 struct MedianFinder {
     small_heap: BinaryHeap<i32>,           // max-heap for smaller half
     large_heap: BinaryHeap<Reverse<i32>>,  // min-heap for larger half
diff --git a/articles/find-polygon-with-the-largest-perimeter.md b/articles/find-polygon-with-the-largest-perimeter.md
@@ -718,8 +718,6 @@ struct Heap<T> {
 ```
 
 ```rust
-use std::cmp::Reverse;
-
 impl Solution {
     pub fn largest_perimeter(nums: Vec<i32>) -> i64 {
         let mut max_heap = BinaryHeap::new();
diff --git a/articles/first-unique-number.md b/articles/first-unique-number.md
@@ -1010,8 +1010,6 @@ class FirstUnique {
 ```
 
 ```rust
-use std::collections::BTreeSet;
-
 struct FirstUnique {
     set_queue: BTreeSet<(usize, i32)>,  // (insertion order, value)
     is_unique: HashMap<i32, bool>,
diff --git a/articles/level-order-traversal-of-binary-tree.md b/articles/level-order-traversal-of-binary-tree.md
@@ -323,9 +323,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn level_order(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<Vec<i32>> {
         let mut res = Vec::new();
@@ -717,10 +714,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::collections::VecDeque;
-use std::rc::Rc;
-
 impl Solution {
     pub fn level_order(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<Vec<i32>> {
         let mut res = Vec::new();
diff --git a/articles/lfu-cache.md b/articles/lfu-cache.md
@@ -497,8 +497,6 @@ class LFUCache {
 ```
 
 ```rust
-use std::collections::HashMap;
-
 struct LFUCache {
     capacity: usize,
     timestamp: i32,
@@ -1503,8 +1501,6 @@ class LFUCache {
 ```
 
 ```rust
-use std::collections::HashMap;
-
 struct DLNode {
     val: i32,
     prev: usize,
diff --git a/articles/serialize-and-deserialize-binary-tree.md b/articles/serialize-and-deserialize-binary-tree.md
@@ -507,9 +507,6 @@ class Codec {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 // Definition for a binary tree node.
 // #[derive(Debug, PartialEq, Eq)]
 // pub struct TreeNode {
@@ -1137,10 +1134,6 @@ class Codec {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::collections::VecDeque;
-use std::rc::Rc;
-
 // Definition for a binary tree node.
 // #[derive(Debug, PartialEq, Eq)]
 // pub struct TreeNode {
diff --git a/articles/stickers-to-spell-word.md b/articles/stickers-to-spell-word.md
@@ -482,8 +482,6 @@ class Solution {
 ```
 
 ```rust
-use std::collections::HashMap;
-
 impl Solution {
     pub fn min_stickers(stickers: Vec<String>, target: String) -> i32 {
         let stick_count: Vec<HashMap<u8, i32>> = stickers
@@ -1009,8 +1007,6 @@ class Solution {
 ```
 
 ```rust
-use std::collections::HashMap;
-
 impl Solution {
     pub fn min_stickers(stickers: Vec<String>, target: String) -> i32 {
         let stick_count: Vec<HashMap<u8, i32>> = stickers
diff --git a/articles/sum-root-to-leaf-numbers.md b/articles/sum-root-to-leaf-numbers.md
@@ -259,9 +259,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn sum_numbers(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         fn dfs(cur: &Option<Rc<RefCell<TreeNode>>>, num: i32) -> i32 {
@@ -593,10 +590,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::collections::VecDeque;
-use std::rc::Rc;
-
 impl Solution {
     pub fn sum_numbers(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let root = match root {
@@ -955,9 +948,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn sum_numbers(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let mut res = 0;
@@ -1437,9 +1427,6 @@ class Solution {
 ```
 
 ```rust
-use std::cell::RefCell;
-use std::rc::Rc;
-
 impl Solution {
     pub fn sum_numbers(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
         let mut res = 0;
