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@ -1,22 +1,36 @@
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use std::cmp::Ordering;
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use std::fmt::{Display, Formatter};
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use std::vec::IntoIter;
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#[derive(Debug)]
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#[derive(Debug, Eq)]
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pub struct BinarySearchTree<T: Ord> {
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root: Child<T>,
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root: HeapNode<T>,
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size: usize,
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}
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type Child<T> = Option<Box<Node<T>>>;
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#[derive(Debug)]
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#[derive(Debug, Eq)]
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struct Node<T: Ord> {
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value: T,
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left: Child<T>,
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right: Child<T>,
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left: HeapNode<T>,
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right: HeapNode<T>,
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}
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type HeapNode<T> = Option<Box<Node<T>>>;
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impl<T: Ord + Display> Display for Node<T> {
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fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
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write!(f, "{}", self.value)
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}
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}
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impl<T: Ord> PartialEq for Node<T> {
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fn eq(&self, other: &Self) -> bool {
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self.value == other.value
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}
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}
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impl<T: Ord> Node<T> {
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fn new(value: T) -> Self {
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fn new(value: T) -> Node<T> {
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Node {
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value,
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left: None,
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@ -24,21 +38,27 @@ impl<T: Ord> Node<T> {
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}
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}
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fn insert(&mut self, value: T) {
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fn insert(&mut self, value: T) -> bool {
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match value.cmp(&self.value) {
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Ordering::Equal => {}
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Ordering::Equal => false,
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Ordering::Less => match self.left {
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None => self.left = Some(Box::from(Node::new(value))),
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None => {
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self.left = Some(Box::from(Node::new(value)));
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true
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}
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Some(ref mut node) => node.insert(value),
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},
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Ordering::Greater => match self.right {
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None => self.right = Some(Box::from(Node::new(value))),
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None => {
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self.right = Some(Box::from(Node::new(value)));
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true
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}
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Some(ref mut node) => node.insert(value),
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},
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}
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}
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fn contains(&self, value: T) -> bool {
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fn contains(&self, value: &T) -> bool {
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match value.cmp(&self.value) {
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Ordering::Equal => true,
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Ordering::Less => match self.left {
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@ -80,169 +100,158 @@ impl<T: Ord> Node<T> {
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}
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}
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// https://users.rust-lang.org/t/binary-search-tree-node-removal-without-unsafe-code/56078
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fn remove(mut root: &mut Child<T>, value: T) {
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while let Some(ref mut node) = root {
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match node.value.cmp(&value) {
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Ordering::Less => root = &mut root.as_mut().unwrap().right,
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Ordering::Greater => root = &mut root.as_mut().unwrap().left,
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Ordering::Equal => match (node.left.as_mut(), node.right.as_mut()) {
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(None, None) => *root = None,
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(Some(_), None) => *root = node.left.take(),
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(None, Some(_)) => *root = node.right.take(),
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(Some(_), Some(_)) => {
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root.as_mut().unwrap().value = Self::extract_min(&mut node.right).unwrap()
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fn remove(root: &mut HeapNode<T>, value: &T) -> bool {
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if let Some(ref mut node) = root {
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return match value.cmp(&node.value) {
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Ordering::Less => Node::remove(&mut node.left, value),
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Ordering::Greater => Node::remove(&mut node.right, value),
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Ordering::Equal => {
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match (&node.left, &node.right) {
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(None, None) => *root = None,
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(Some(_), None) => *root = node.left.take(),
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(None, Some(_)) => *root = node.right.take(),
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(Some(_), Some(_)) => node.value = Node::extract_min(&mut node.right),
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}
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},
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}
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}
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}
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// https://users.rust-lang.org/t/binary-search-tree-node-removal-without-unsafe-code/56078
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fn extract_min(node: &mut Child<T>) -> Option<T> {
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let mut value = None;
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if node.is_some() {
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let mut current = node;
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true
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}
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};
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}
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while current.as_ref().unwrap().left.is_some() {
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current = &mut current.as_mut().unwrap().left;
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}
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false
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}
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let node = current.take().unwrap();
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value = Some(node.value);
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*current = node.right;
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fn extract_min(root: &mut HeapNode<T>) -> T {
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if root.as_ref().unwrap().left.is_some() {
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Node::extract_min(&mut root.as_mut().unwrap().left)
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} else {
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let node = root.take().unwrap();
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*root = node.right;
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node.value
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}
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value
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}
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fn pre_order_traversal<'a>(node: &'a Child<T>, elements: &mut Vec<&'a T>) {
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fn pre_order_traversal<'a>(node: &'a HeapNode<T>, elements: &mut Vec<&'a T>) {
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if let Some(ref node) = node {
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elements.push(&node.value);
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Self::pre_order_traversal(&node.left, elements);
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Self::pre_order_traversal(&node.right, elements);
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Node::pre_order_traversal(&node.left, elements);
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Node::pre_order_traversal(&node.right, elements);
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}
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}
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fn in_order_traversal<'a>(node: &'a Child<T>, elements: &mut Vec<&'a T>) {
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fn in_order_traversal<'a>(node: &'a HeapNode<T>, elements: &mut Vec<&'a T>) {
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if let Some(ref node) = node {
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Self::in_order_traversal(&node.left, elements);
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Node::in_order_traversal(&node.left, elements);
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elements.push(&node.value);
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Self::in_order_traversal(&node.right, elements);
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Node::in_order_traversal(&node.right, elements);
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}
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}
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fn post_order_traversal<'a>(node: &'a Child<T>, elements: &mut Vec<&'a T>) {
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fn post_order_traversal<'a>(node: &'a HeapNode<T>, elements: &mut Vec<&'a T>) {
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if let Some(ref node) = node {
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Self::post_order_traversal(&node.left, elements);
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Self::post_order_traversal(&node.right, elements);
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Node::post_order_traversal(&node.left, elements);
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Node::post_order_traversal(&node.right, elements);
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elements.push(&node.value);
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}
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}
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fn into_pre_order_traversal(node: Child<T>, elements: &mut Vec<T>) {
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fn into_pre_order_traversal(node: HeapNode<T>, elements: &mut Vec<T>) {
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if let Some(node) = node {
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elements.push(node.value);
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Self::into_pre_order_traversal(node.left, elements);
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Self::into_pre_order_traversal(node.right, elements);
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Node::into_pre_order_traversal(node.left, elements);
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Node::into_pre_order_traversal(node.right, elements);
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}
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}
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fn into_in_order_traversal(node: Child<T>, elements: &mut Vec<T>) {
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fn into_in_order_traversal(node: HeapNode<T>, elements: &mut Vec<T>) {
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if let Some(node) = node {
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Self::into_in_order_traversal(node.left, elements);
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Node::into_in_order_traversal(node.left, elements);
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elements.push(node.value);
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Self::into_in_order_traversal(node.right, elements);
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Node::into_in_order_traversal(node.right, elements);
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}
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}
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fn into_post_order_traversal(node: Child<T>, elements: &mut Vec<T>) {
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fn into_post_order_traversal(node: HeapNode<T>, elements: &mut Vec<T>) {
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if let Some(node) = node {
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Self::into_post_order_traversal(node.left, elements);
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Self::into_post_order_traversal(node.right, elements);
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Node::into_post_order_traversal(node.left, elements);
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Node::into_post_order_traversal(node.right, elements);
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elements.push(node.value);
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}
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}
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}
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impl<T: Ord + Copy> Node<T> {
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fn pre_order_traversal_copy(node: &Child<T>, elements: &mut Vec<T>) {
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if let Some(ref node) = node {
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elements.push(node.value);
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Self::pre_order_traversal_copy(&node.left, elements);
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Self::pre_order_traversal_copy(&node.right, elements);
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}
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}
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fn in_order_traversal_copy(node: &Child<T>, elements: &mut Vec<T>) {
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if let Some(ref node) = node {
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Self::in_order_traversal_copy(&node.left, elements);
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elements.push(node.value);
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Self::in_order_traversal_copy(&node.right, elements);
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impl<T: Ord + Display> Display for BinarySearchTree<T> {
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fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
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write!(f, "[")?;
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let vec = self.in_order_iter();
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let len = vec.len();
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for (index, elem) in vec.enumerate() {
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if index == len - 1 {
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write!(f, "{}", elem)?;
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} else {
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write!(f, "{}, ", elem)?;
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}
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}
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}
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fn post_order_traversal_copy(node: &Child<T>, elements: &mut Vec<T>) {
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if let Some(ref node) = node {
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Self::post_order_traversal_copy(&node.left, elements);
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Self::post_order_traversal_copy(&node.right, elements);
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elements.push(node.value);
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}
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write!(f, "]")
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}
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}
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impl<T: Ord + Copy> BinarySearchTree<T> {
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pub fn pre_order(&self) -> Vec<T> {
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let mut elements: Vec<T> = Vec::new();
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Node::pre_order_traversal_copy(&self.root, &mut elements);
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elements
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}
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pub fn in_order(&self) -> Vec<T> {
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let mut elements: Vec<T> = Vec::new();
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Node::in_order_traversal_copy(&self.root, &mut elements);
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elements
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}
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pub fn post_order(&self) -> Vec<T> {
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let mut elements: Vec<T> = Vec::new();
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Node::post_order_traversal_copy(&self.root, &mut elements);
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elements
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impl<T: Ord> PartialEq for BinarySearchTree<T> {
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fn eq(&self, other: &Self) -> bool {
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self.in_order() == other.in_order()
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}
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}
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impl<T: Ord> BinarySearchTree<T> {
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pub fn empty() -> Self {
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Self { root: None }
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pub fn empty() -> BinarySearchTree<T> {
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BinarySearchTree {
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root: None,
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size: 0,
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}
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}
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pub fn new(value: T) -> Self {
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Self {
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pub fn new(value: T) -> BinarySearchTree<T> {
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BinarySearchTree {
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root: Some(Box::from(Node::new(value))),
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size: 1,
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}
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}
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pub fn size(&self) -> usize {
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self.size
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}
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pub fn is_empty(&self) -> bool {
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self.root.is_none()
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}
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pub fn insert(&mut self, value: T) {
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match self.root {
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None => self.root = Some(Box::from(Node::new(value))),
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Some(ref mut node) => node.insert(value),
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None => {
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self.root = Some(Box::from(Node::new(value)));
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self.size += 1;
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}
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Some(ref mut node) => {
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if node.insert(value) {
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self.size += 1;
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}
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}
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}
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}
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pub fn contains(&self, value: T) -> bool {
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pub fn contains(&self, value: &T) -> bool {
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match self.root {
|
|
|
|
|
None => false,
|
|
|
|
|
Some(ref node) => node.contains(value),
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
pub fn remove(&mut self, value: T) {
|
|
|
|
|
Node::remove(&mut self.root, value);
|
|
|
|
|
pub fn remove(&mut self, value: &T) {
|
|
|
|
|
if Node::remove(&mut self.root, value) {
|
|
|
|
|
self.size -= 1;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
pub fn retrieve(&self, value: T) -> Option<&T> {
|
|
|
|
@ -259,6 +268,24 @@ impl<T: Ord> BinarySearchTree<T> {
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
pub fn pre_order(&self) -> Vec<&T> {
|
|
|
|
|
let mut elements: Vec<&T> = Vec::new();
|
|
|
|
|
Node::pre_order_traversal(&self.root, &mut elements);
|
|
|
|
|
elements
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
pub fn in_order(&self) -> Vec<&T> {
|
|
|
|
|
let mut elements: Vec<&T> = Vec::new();
|
|
|
|
|
Node::in_order_traversal(&self.root, &mut elements);
|
|
|
|
|
elements
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
pub fn post_order(&self) -> Vec<&T> {
|
|
|
|
|
let mut elements: Vec<&T> = Vec::new();
|
|
|
|
|
Node::post_order_traversal(&self.root, &mut elements);
|
|
|
|
|
elements
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
pub fn pre_order_iter(&self) -> IntoIter<&T> {
|
|
|
|
|
let mut elements: Vec<&T> = Vec::new();
|
|
|
|
|
Node::pre_order_traversal(&self.root, &mut elements);
|
|
|
|
@ -327,10 +354,7 @@ mod bst_test {
|
|
|
|
|
bst.insert(1);
|
|
|
|
|
bst.insert(2);
|
|
|
|
|
|
|
|
|
|
assert_eq!(bst.retrieve(-1), Some(&-1));
|
|
|
|
|
assert_eq!(bst.retrieve(0), Some(&0));
|
|
|
|
|
assert_eq!(bst.retrieve(1), Some(&1));
|
|
|
|
|
assert_eq!(bst.retrieve(2), Some(&2));
|
|
|
|
|
assert_eq!(bst.size(), 4);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
@ -349,9 +373,9 @@ mod bst_test {
|
|
|
|
|
bst.insert(1);
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
|
|
|
|
|
assert!(!bst.contains(10));
|
|
|
|
|
assert!(bst.contains(1));
|
|
|
|
|
assert!(bst.contains(5));
|
|
|
|
|
assert!(!bst.contains(&10));
|
|
|
|
|
assert!(bst.contains(&1));
|
|
|
|
|
assert!(bst.contains(&5));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
@ -359,83 +383,112 @@ mod bst_test {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(0);
|
|
|
|
|
|
|
|
|
|
bst.remove(0);
|
|
|
|
|
assert!(!bst.is_empty());
|
|
|
|
|
assert_eq!(bst.size(), 1);
|
|
|
|
|
|
|
|
|
|
bst.remove(&0);
|
|
|
|
|
|
|
|
|
|
assert!(bst.is_empty())
|
|
|
|
|
assert!(bst.is_empty());
|
|
|
|
|
assert_eq!(bst.size(), 0)
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn remove_leaf_node() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
bst.insert(4);
|
|
|
|
|
bst.insert(6);
|
|
|
|
|
bst.insert(7);
|
|
|
|
|
let mut expected_bst = BinarySearchTree::empty();
|
|
|
|
|
expected_bst.insert(5);
|
|
|
|
|
expected_bst.insert(4);
|
|
|
|
|
expected_bst.insert(6);
|
|
|
|
|
let mut actual_bst = BinarySearchTree::empty();
|
|
|
|
|
actual_bst.insert(5);
|
|
|
|
|
actual_bst.insert(4);
|
|
|
|
|
actual_bst.insert(6);
|
|
|
|
|
actual_bst.insert(7);
|
|
|
|
|
|
|
|
|
|
bst.remove(7);
|
|
|
|
|
actual_bst.remove(&7);
|
|
|
|
|
|
|
|
|
|
assert!(!bst.contains(7));
|
|
|
|
|
assert_eq!(bst.in_order(), vec![4, 5, 6])
|
|
|
|
|
assert_eq!(actual_bst.size(), 3);
|
|
|
|
|
assert_eq!(actual_bst, expected_bst);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn remove_single_right_node_with_children() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
bst.insert(4);
|
|
|
|
|
bst.insert(6);
|
|
|
|
|
bst.insert(7);
|
|
|
|
|
bst.insert(8);
|
|
|
|
|
let mut expected_bst = BinarySearchTree::empty();
|
|
|
|
|
expected_bst.insert(5);
|
|
|
|
|
expected_bst.insert(4);
|
|
|
|
|
expected_bst.insert(7);
|
|
|
|
|
expected_bst.insert(8);
|
|
|
|
|
let mut actual_bst = BinarySearchTree::empty();
|
|
|
|
|
actual_bst.insert(5);
|
|
|
|
|
actual_bst.insert(4);
|
|
|
|
|
actual_bst.insert(6);
|
|
|
|
|
actual_bst.insert(7);
|
|
|
|
|
actual_bst.insert(8);
|
|
|
|
|
|
|
|
|
|
bst.remove(6);
|
|
|
|
|
actual_bst.remove(&6);
|
|
|
|
|
|
|
|
|
|
assert!(!bst.contains(6));
|
|
|
|
|
assert_eq!(bst.in_order(), vec![4, 5, 7, 8])
|
|
|
|
|
assert_eq!(actual_bst.size(), 4);
|
|
|
|
|
assert_eq!(actual_bst, expected_bst);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn remove_single_left_node_with_children() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
bst.insert(4);
|
|
|
|
|
bst.insert(6);
|
|
|
|
|
bst.insert(3);
|
|
|
|
|
bst.insert(2);
|
|
|
|
|
let mut expected_bst = BinarySearchTree::empty();
|
|
|
|
|
expected_bst.insert(5);
|
|
|
|
|
expected_bst.insert(3);
|
|
|
|
|
expected_bst.insert(2);
|
|
|
|
|
expected_bst.insert(6);
|
|
|
|
|
let mut actual_bst = BinarySearchTree::empty();
|
|
|
|
|
actual_bst.insert(5);
|
|
|
|
|
actual_bst.insert(4);
|
|
|
|
|
actual_bst.insert(6);
|
|
|
|
|
actual_bst.insert(3);
|
|
|
|
|
actual_bst.insert(2);
|
|
|
|
|
|
|
|
|
|
bst.remove(4);
|
|
|
|
|
actual_bst.remove(&4);
|
|
|
|
|
|
|
|
|
|
assert!(!bst.contains(4));
|
|
|
|
|
assert_eq!(bst.in_order(), vec![2, 3, 5, 6])
|
|
|
|
|
assert_eq!(actual_bst.size(), 4);
|
|
|
|
|
assert_eq!(actual_bst, expected_bst);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn remove_node_with_two_children() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(10);
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
bst.insert(8);
|
|
|
|
|
bst.insert(3);
|
|
|
|
|
bst.insert(15);
|
|
|
|
|
let mut expected_bst = BinarySearchTree::empty();
|
|
|
|
|
expected_bst.insert(10);
|
|
|
|
|
expected_bst.insert(3);
|
|
|
|
|
expected_bst.insert(8);
|
|
|
|
|
expected_bst.insert(15);
|
|
|
|
|
let mut actual_bst = BinarySearchTree::empty();
|
|
|
|
|
actual_bst.insert(10);
|
|
|
|
|
actual_bst.insert(5);
|
|
|
|
|
actual_bst.insert(8);
|
|
|
|
|
actual_bst.insert(3);
|
|
|
|
|
actual_bst.insert(15);
|
|
|
|
|
|
|
|
|
|
bst.remove(5);
|
|
|
|
|
actual_bst.remove(&5);
|
|
|
|
|
|
|
|
|
|
assert!(!bst.contains(5));
|
|
|
|
|
assert_eq!(bst.in_order(), vec![3, 8, 10, 15])
|
|
|
|
|
assert_eq!(actual_bst, expected_bst);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn does_not_fail_when_removing_non_existing_element() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(10);
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
bst.insert(8);
|
|
|
|
|
bst.insert(3);
|
|
|
|
|
bst.insert(15);
|
|
|
|
|
let mut expected_bst = BinarySearchTree::empty();
|
|
|
|
|
expected_bst.insert(10);
|
|
|
|
|
expected_bst.insert(5);
|
|
|
|
|
expected_bst.insert(8);
|
|
|
|
|
expected_bst.insert(3);
|
|
|
|
|
expected_bst.insert(15);
|
|
|
|
|
|
|
|
|
|
bst.remove(20);
|
|
|
|
|
let mut actual_bst = BinarySearchTree::empty();
|
|
|
|
|
actual_bst.insert(10);
|
|
|
|
|
actual_bst.insert(5);
|
|
|
|
|
actual_bst.insert(8);
|
|
|
|
|
actual_bst.insert(3);
|
|
|
|
|
actual_bst.insert(15);
|
|
|
|
|
|
|
|
|
|
assert!(!bst.contains(20));
|
|
|
|
|
assert_eq!(bst.in_order(), vec![3, 5, 8, 10, 15])
|
|
|
|
|
actual_bst.remove(&20);
|
|
|
|
|
|
|
|
|
|
assert_eq!(actual_bst.size(), 5);
|
|
|
|
|
assert_eq!(actual_bst, expected_bst);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
@ -453,16 +506,18 @@ mod bst_test {
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn retrieve_element_as_mut_and_modify_bst() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(10);
|
|
|
|
|
bst.insert(5);
|
|
|
|
|
let mut expected_bst = BinarySearchTree::empty();
|
|
|
|
|
expected_bst.insert(10);
|
|
|
|
|
expected_bst.insert(2);
|
|
|
|
|
|
|
|
|
|
let mut actual_bst = BinarySearchTree::empty();
|
|
|
|
|
actual_bst.insert(10);
|
|
|
|
|
actual_bst.insert(5);
|
|
|
|
|
|
|
|
|
|
let _retrieved_value_as_mut: &mut i32 = bst.retrieve_as_mut(5).unwrap();
|
|
|
|
|
let _retrieved_value_as_mut: &mut i32 = actual_bst.retrieve_as_mut(5).unwrap();
|
|
|
|
|
*_retrieved_value_as_mut = 2;
|
|
|
|
|
|
|
|
|
|
assert!(bst.contains(10));
|
|
|
|
|
assert!(bst.contains(2));
|
|
|
|
|
assert!(!bst.contains(5));
|
|
|
|
|
assert_eq!(actual_bst, expected_bst);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
@ -617,7 +672,7 @@ mod bst_test {
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn pre_order_traversal_copy() {
|
|
|
|
|
fn pre_order() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(3);
|
|
|
|
|
bst.insert(4);
|
|
|
|
@ -625,11 +680,11 @@ mod bst_test {
|
|
|
|
|
bst.insert(1);
|
|
|
|
|
bst.insert(2);
|
|
|
|
|
|
|
|
|
|
assert_eq!(bst.pre_order(), vec![3, 1, 2, 4, 5]);
|
|
|
|
|
assert_eq!(bst.pre_order(), vec![&3, &1, &2, &4, &5]);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn in_order_traversal_copy() {
|
|
|
|
|
fn in_order() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(3);
|
|
|
|
|
bst.insert(4);
|
|
|
|
@ -637,11 +692,11 @@ mod bst_test {
|
|
|
|
|
bst.insert(1);
|
|
|
|
|
bst.insert(2);
|
|
|
|
|
|
|
|
|
|
assert_eq!(bst.in_order(), vec![1, 2, 3, 4, 5]);
|
|
|
|
|
assert_eq!(bst.in_order(), vec![&1, &2, &3, &4, &5]);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
|
fn post_order_traversal_copy() {
|
|
|
|
|
fn post_order() {
|
|
|
|
|
let mut bst = BinarySearchTree::empty();
|
|
|
|
|
bst.insert(3);
|
|
|
|
|
bst.insert(4);
|
|
|
|
@ -649,6 +704,6 @@ mod bst_test {
|
|
|
|
|
bst.insert(1);
|
|
|
|
|
bst.insert(2);
|
|
|
|
|
|
|
|
|
|
assert_eq!(bst.post_order(), vec![2, 1, 5, 4, 3]);
|
|
|
|
|
assert_eq!(bst.post_order(), vec![&2, &1, &5, &4, &3]);
|
|
|
|
|
}
|
|
|
|
|
}
|