From faa08e2bd410627668769e83c51bb482302db90d Mon Sep 17 00:00:00 2001
From: Antim Pal <134076504+iamAntimPal@users.noreply.github.com>
Date: Tue, 15 Apr 2025 07:05:17 +0530
Subject: [PATCH 1/5] Create 208. Implement Trie (Prefix Tree).py
Co-Authored-By: Antim-IWP <203163676+Antim-IWP@users.noreply.github.com>
Co-Authored-By: Shiwangi Srivastava <174641070+IamShiwangi@users.noreply.github.com>
---
.../208. Implement Trie (Prefix Tree).py | 0
1 file changed, 0 insertions(+), 0 deletions(-)
create mode 100644 Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py
diff --git a/Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py b/Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py
new file mode 100644
index 0000000..e69de29
From 147684bd514176a4c9ff0ecc21640efbbc3a47ed Mon Sep 17 00:00:00 2001
From: Antim Pal <134076504+iamAntimPal@users.noreply.github.com>
Date: Tue, 15 Apr 2025 07:05:25 +0530
Subject: [PATCH 2/5] Update 208. Implement Trie (Prefix Tree).py
Co-Authored-By: Antim-IWP <203163676+Antim-IWP@users.noreply.github.com>
Co-Authored-By: Shiwangi Srivastava <174641070+IamShiwangi@users.noreply.github.com>
---
.../208. Implement Trie (Prefix Tree).py | 37 +++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py b/Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py
index e69de29..286796c 100644
--- a/Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py
+++ b/Solution/208. Implement Trie (Prefix Tree)/208. Implement Trie (Prefix Tree).py
@@ -0,0 +1,37 @@
+class Trie:
+ def __init__(self):
+ self.children = [None] * 26
+ self.is_end = False
+
+ def insert(self, word: str) -> None:
+ node = self
+ for c in word:
+ idx = ord(c) - ord('a')
+ if node.children[idx] is None:
+ node.children[idx] = Trie()
+ node = node.children[idx]
+ node.is_end = True
+
+ def search(self, word: str) -> bool:
+ node = self._search_prefix(word)
+ return node is not None and node.is_end
+
+ def startsWith(self, prefix: str) -> bool:
+ node = self._search_prefix(prefix)
+ return node is not None
+
+ def _search_prefix(self, prefix: str):
+ node = self
+ for c in prefix:
+ idx = ord(c) - ord('a')
+ if node.children[idx] is None:
+ return None
+ node = node.children[idx]
+ return node
+
+
+# Your Trie object will be instantiated and called as such:
+# obj = Trie()
+# obj.insert(word)
+# param_2 = obj.search(word)
+# param_3 = obj.startsWith(prefix)
\ No newline at end of file
From d4e554d8a937ff71088be89b9ab3e3981ac4fb45 Mon Sep 17 00:00:00 2001
From: Antim Pal <134076504+iamAntimPal@users.noreply.github.com>
Date: Tue, 15 Apr 2025 07:05:45 +0530
Subject: [PATCH 3/5] Create readme.md
Co-Authored-By: Antim-IWP <203163676+Antim-IWP@users.noreply.github.com>
Co-Authored-By: Shiwangi Srivastava <174641070+IamShiwangi@users.noreply.github.com>
---
Solution/208. Implement Trie (Prefix Tree)/readme.md | 0
1 file changed, 0 insertions(+), 0 deletions(-)
create mode 100644 Solution/208. Implement Trie (Prefix Tree)/readme.md
diff --git a/Solution/208. Implement Trie (Prefix Tree)/readme.md b/Solution/208. Implement Trie (Prefix Tree)/readme.md
new file mode 100644
index 0000000..e69de29
From 603bd68356284767ba6e5122670658344886ae83 Mon Sep 17 00:00:00 2001
From: Antim Pal <134076504+iamAntimPal@users.noreply.github.com>
Date: Tue, 15 Apr 2025 07:05:50 +0530
Subject: [PATCH 4/5] Update readme.md
Co-Authored-By: Antim-IWP <203163676+Antim-IWP@users.noreply.github.com>
Co-Authored-By: Shiwangi Srivastava <174641070+IamShiwangi@users.noreply.github.com>
---
.../readme.md | 549 ++++++++++++++++++
1 file changed, 549 insertions(+)
diff --git a/Solution/208. Implement Trie (Prefix Tree)/readme.md b/Solution/208. Implement Trie (Prefix Tree)/readme.md
index e69de29..fe82e7b 100644
--- a/Solution/208. Implement Trie (Prefix Tree)/readme.md
+++ b/Solution/208. Implement Trie (Prefix Tree)/readme.md
@@ -0,0 +1,549 @@
+---
+comments: true
+difficulty: Medium
+edit_url: https://github.com/doocs/leetcode/edit/main/solution/0200-0299/0208.Implement%20Trie%20%28Prefix%20Tree%29/README_EN.md
+tags:
+ - Design
+ - Trie
+ - Hash Table
+ - String
+---
+
+
+
+# [208. Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree)
+
+[中文文档](/solution/0200-0299/0208.Implement%20Trie%20%28Prefix%20Tree%29/README.md)
+
+## Description
+
+
+
+A trie (pronounced as "try") or prefix tree is a tree data structure used to efficiently store and retrieve keys in a dataset of strings. There are various applications of this data structure, such as autocomplete and spellchecker.
+
+Implement the Trie class:
+
+
+ Trie() Initializes the trie object.void insert(String word) Inserts the string word into the trie.boolean search(String word) Returns true if the string word is in the trie (i.e., was inserted before), and false otherwise.boolean startsWith(String prefix) Returns true if there is a previously inserted string word that has the prefix prefix, and false otherwise.
+
+
+Example 1:
+
+
+Input
+["Trie", "insert", "search", "search", "startsWith", "insert", "search"]
+[[], ["apple"], ["apple"], ["app"], ["app"], ["app"], ["app"]]
+Output
+[null, null, true, false, true, null, true]
+
+Explanation
+Trie trie = new Trie();
+trie.insert("apple");
+trie.search("apple"); // return True
+trie.search("app"); // return False
+trie.startsWith("app"); // return True
+trie.insert("app");
+trie.search("app"); // return True
+
+
+
+Constraints:
+
+
+ 1 <= word.length, prefix.length <= 2000word and prefix consist only of lowercase English letters.- At most
3 * 104 calls in total will be made to insert, search, and startsWith.
+
+
+
+
+## Solutions
+
+
+
+### Solution 1
+
+
+
+#### Python3
+
+```python
+class Trie:
+ def __init__(self):
+ self.children = [None] * 26
+ self.is_end = False
+
+ def insert(self, word: str) -> None:
+ node = self
+ for c in word:
+ idx = ord(c) - ord('a')
+ if node.children[idx] is None:
+ node.children[idx] = Trie()
+ node = node.children[idx]
+ node.is_end = True
+
+ def search(self, word: str) -> bool:
+ node = self._search_prefix(word)
+ return node is not None and node.is_end
+
+ def startsWith(self, prefix: str) -> bool:
+ node = self._search_prefix(prefix)
+ return node is not None
+
+ def _search_prefix(self, prefix: str):
+ node = self
+ for c in prefix:
+ idx = ord(c) - ord('a')
+ if node.children[idx] is None:
+ return None
+ node = node.children[idx]
+ return node
+
+
+# Your Trie object will be instantiated and called as such:
+# obj = Trie()
+# obj.insert(word)
+# param_2 = obj.search(word)
+# param_3 = obj.startsWith(prefix)
+```
+
+#### Java
+
+```java
+class Trie {
+ private Trie[] children;
+ private boolean isEnd;
+
+ public Trie() {
+ children = new Trie[26];
+ }
+
+ public void insert(String word) {
+ Trie node = this;
+ for (char c : word.toCharArray()) {
+ int idx = c - 'a';
+ if (node.children[idx] == null) {
+ node.children[idx] = new Trie();
+ }
+ node = node.children[idx];
+ }
+ node.isEnd = true;
+ }
+
+ public boolean search(String word) {
+ Trie node = searchPrefix(word);
+ return node != null && node.isEnd;
+ }
+
+ public boolean startsWith(String prefix) {
+ Trie node = searchPrefix(prefix);
+ return node != null;
+ }
+
+ private Trie searchPrefix(String s) {
+ Trie node = this;
+ for (char c : s.toCharArray()) {
+ int idx = c - 'a';
+ if (node.children[idx] == null) {
+ return null;
+ }
+ node = node.children[idx];
+ }
+ return node;
+ }
+}
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * Trie obj = new Trie();
+ * obj.insert(word);
+ * boolean param_2 = obj.search(word);
+ * boolean param_3 = obj.startsWith(prefix);
+ */
+```
+
+#### C++
+
+```cpp
+class Trie {
+private:
+ vector children;
+ bool isEnd;
+
+ Trie* searchPrefix(string s) {
+ Trie* node = this;
+ for (char c : s) {
+ int idx = c - 'a';
+ if (!node->children[idx]) return nullptr;
+ node = node->children[idx];
+ }
+ return node;
+ }
+
+public:
+ Trie()
+ : children(26)
+ , isEnd(false) {}
+
+ void insert(string word) {
+ Trie* node = this;
+ for (char c : word) {
+ int idx = c - 'a';
+ if (!node->children[idx]) node->children[idx] = new Trie();
+ node = node->children[idx];
+ }
+ node->isEnd = true;
+ }
+
+ bool search(string word) {
+ Trie* node = searchPrefix(word);
+ return node != nullptr && node->isEnd;
+ }
+
+ bool startsWith(string prefix) {
+ Trie* node = searchPrefix(prefix);
+ return node != nullptr;
+ }
+};
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * Trie* obj = new Trie();
+ * obj->insert(word);
+ * bool param_2 = obj->search(word);
+ * bool param_3 = obj->startsWith(prefix);
+ */
+```
+
+#### Go
+
+```go
+type Trie struct {
+ children [26]*Trie
+ isEnd bool
+}
+
+func Constructor() Trie {
+ return Trie{}
+}
+
+func (this *Trie) Insert(word string) {
+ node := this
+ for _, c := range word {
+ idx := c - 'a'
+ if node.children[idx] == nil {
+ node.children[idx] = &Trie{}
+ }
+ node = node.children[idx]
+ }
+ node.isEnd = true
+}
+
+func (this *Trie) Search(word string) bool {
+ node := this.SearchPrefix(word)
+ return node != nil && node.isEnd
+}
+
+func (this *Trie) StartsWith(prefix string) bool {
+ node := this.SearchPrefix(prefix)
+ return node != nil
+}
+
+func (this *Trie) SearchPrefix(s string) *Trie {
+ node := this
+ for _, c := range s {
+ idx := c - 'a'
+ if node.children[idx] == nil {
+ return nil
+ }
+ node = node.children[idx]
+ }
+ return node
+}
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * obj := Constructor();
+ * obj.Insert(word);
+ * param_2 := obj.Search(word);
+ * param_3 := obj.StartsWith(prefix);
+ */
+```
+
+#### TypeScript
+
+```ts
+class TrieNode {
+ children;
+ isEnd;
+ constructor() {
+ this.children = new Array(26);
+ this.isEnd = false;
+ }
+}
+
+class Trie {
+ root;
+ constructor() {
+ this.root = new TrieNode();
+ }
+
+ insert(word: string): void {
+ let head = this.root;
+ for (let char of word) {
+ let index = char.charCodeAt(0) - 97;
+ if (!head.children[index]) {
+ head.children[index] = new TrieNode();
+ }
+ head = head.children[index];
+ }
+ head.isEnd = true;
+ }
+
+ search(word: string): boolean {
+ let head = this.searchPrefix(word);
+ return head != null && head.isEnd;
+ }
+
+ startsWith(prefix: string): boolean {
+ return this.searchPrefix(prefix) != null;
+ }
+
+ private searchPrefix(prefix: string) {
+ let head = this.root;
+ for (let char of prefix) {
+ let index = char.charCodeAt(0) - 97;
+ if (!head.children[index]) return null;
+ head = head.children[index];
+ }
+ return head;
+ }
+}
+```
+
+#### Rust
+
+```rust
+use std::{cell::RefCell, collections::HashMap, rc::Rc};
+
+struct TrieNode {
+ pub val: Option,
+ pub flag: bool,
+ pub child: HashMap>>,
+}
+
+impl TrieNode {
+ fn new() -> Self {
+ Self {
+ val: None,
+ flag: false,
+ child: HashMap::new(),
+ }
+ }
+
+ fn new_with_val(val: char) -> Self {
+ Self {
+ val: Some(val),
+ flag: false,
+ child: HashMap::new(),
+ }
+ }
+}
+
+struct Trie {
+ root: Rc>,
+}
+
+/// Your Trie object will be instantiated and called as such:
+/// let obj = Trie::new();
+/// obj.insert(word);
+/// let ret_2: bool = obj.search(word);
+/// let ret_3: bool = obj.starts_with(prefix);
+impl Trie {
+ fn new() -> Self {
+ Self {
+ root: Rc::new(RefCell::new(TrieNode::new())),
+ }
+ }
+
+ fn insert(&self, word: String) {
+ let char_vec: Vec = word.chars().collect();
+ // Get the clone of current root node
+ let mut root = Rc::clone(&self.root);
+ for c in &char_vec {
+ if !root.borrow().child.contains_key(c) {
+ // We need to manually create the entry
+ root.borrow_mut()
+ .child
+ .insert(*c, Rc::new(RefCell::new(TrieNode::new())));
+ }
+ // Get the child node
+ let root_clone = Rc::clone(root.borrow().child.get(c).unwrap());
+ root = root_clone;
+ }
+ {
+ root.borrow_mut().flag = true;
+ }
+ }
+
+ fn search(&self, word: String) -> bool {
+ let char_vec: Vec = word.chars().collect();
+ // Get the clone of current root node
+ let mut root = Rc::clone(&self.root);
+ for c in &char_vec {
+ if !root.borrow().child.contains_key(c) {
+ return false;
+ }
+ // Get the child node
+ let root_clone = Rc::clone(root.borrow().child.get(c).unwrap());
+ root = root_clone;
+ }
+ let flag = root.borrow().flag;
+ flag
+ }
+
+ fn starts_with(&self, prefix: String) -> bool {
+ let char_vec: Vec = prefix.chars().collect();
+ // Get the clone of current root node
+ let mut root = Rc::clone(&self.root);
+ for c in &char_vec {
+ if !root.borrow().child.contains_key(c) {
+ return false;
+ }
+ // Get the child node
+ let root_clone = Rc::clone(root.borrow().child.get(c).unwrap());
+ root = root_clone;
+ }
+ true
+ }
+}
+```
+
+#### JavaScript
+
+```js
+/**
+ * Initialize your data structure here.
+ */
+var Trie = function () {
+ this.children = {};
+};
+
+/**
+ * Inserts a word into the trie.
+ * @param {string} word
+ * @return {void}
+ */
+Trie.prototype.insert = function (word) {
+ let node = this.children;
+ for (let char of word) {
+ if (!node[char]) {
+ node[char] = {};
+ }
+ node = node[char];
+ }
+ node.isEnd = true;
+};
+
+/**
+ * Returns if the word is in the trie.
+ * @param {string} word
+ * @return {boolean}
+ */
+Trie.prototype.search = function (word) {
+ let node = this.searchPrefix(word);
+ return node != undefined && node.isEnd != undefined;
+};
+
+Trie.prototype.searchPrefix = function (prefix) {
+ let node = this.children;
+ for (let char of prefix) {
+ if (!node[char]) return false;
+ node = node[char];
+ }
+ return node;
+};
+
+/**
+ * Returns if there is any word in the trie that starts with the given prefix.
+ * @param {string} prefix
+ * @return {boolean}
+ */
+Trie.prototype.startsWith = function (prefix) {
+ return this.searchPrefix(prefix);
+};
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * var obj = new Trie()
+ * obj.insert(word)
+ * var param_2 = obj.search(word)
+ * var param_3 = obj.startsWith(prefix)
+ */
+```
+
+#### C#
+
+```cs
+public class Trie {
+ bool isEnd;
+ Trie[] children = new Trie[26];
+
+ public Trie() {
+
+ }
+
+ public void Insert(string word) {
+ Trie node = this;
+ foreach (var c in word)
+ {
+ var idx = c - 'a';
+ node.children[idx] ??= new Trie();
+ node = node.children[idx];
+ }
+ node.isEnd = true;
+ }
+
+ public bool Search(string word) {
+ Trie node = SearchPrefix(word);
+ return node != null && node.isEnd;
+ }
+
+ public bool StartsWith(string prefix) {
+ Trie node = SearchPrefix(prefix);
+ return node != null;
+ }
+
+ private Trie SearchPrefix(string s) {
+ Trie node = this;
+ foreach (var c in s)
+ {
+ var idx = c - 'a';
+ if (node.children[idx] == null)
+ {
+ return null;
+ }
+ node = node.children[idx];
+ }
+ return node;
+ }
+}
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * Trie obj = new Trie();
+ * obj.Insert(word);
+ * bool param_2 = obj.Search(word);
+ * bool param_3 = obj.StartsWith(prefix);
+ */
+```
+
+
+
+
+
+
\ No newline at end of file
From d1ee7417e5cb00509385e7db60b0a700cccda667 Mon Sep 17 00:00:00 2001
From: Antim Pal <134076504+iamAntimPal@users.noreply.github.com>
Date: Tue, 15 Apr 2025 07:06:46 +0530
Subject: [PATCH 5/5] Update readme.md
Co-Authored-By: Antim-IWP <203163676+Antim-IWP@users.noreply.github.com>
Co-Authored-By: Shiwangi Srivastava <174641070+IamShiwangi@users.noreply.github.com>
---
.../readme.md | 326 +-----------------
1 file changed, 1 insertion(+), 325 deletions(-)
diff --git a/Solution/208. Implement Trie (Prefix Tree)/readme.md b/Solution/208. Implement Trie (Prefix Tree)/readme.md
index fe82e7b..399d79b 100644
--- a/Solution/208. Implement Trie (Prefix Tree)/readme.md
+++ b/Solution/208. Implement Trie (Prefix Tree)/readme.md
@@ -1,7 +1,7 @@
---
comments: true
difficulty: Medium
-edit_url: https://github.com/doocs/leetcode/edit/main/solution/0200-0299/0208.Implement%20Trie%20%28Prefix%20Tree%29/README_EN.md
+edit_url: Antim
tags:
- Design
- Trie
@@ -13,7 +13,6 @@ tags:
# [208. Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree)
-[中文文档](/solution/0200-0299/0208.Implement%20Trie%20%28Prefix%20Tree%29/README.md)
## Description
@@ -219,329 +218,6 @@ public:
*/
```
-#### Go
-
-```go
-type Trie struct {
- children [26]*Trie
- isEnd bool
-}
-
-func Constructor() Trie {
- return Trie{}
-}
-
-func (this *Trie) Insert(word string) {
- node := this
- for _, c := range word {
- idx := c - 'a'
- if node.children[idx] == nil {
- node.children[idx] = &Trie{}
- }
- node = node.children[idx]
- }
- node.isEnd = true
-}
-
-func (this *Trie) Search(word string) bool {
- node := this.SearchPrefix(word)
- return node != nil && node.isEnd
-}
-
-func (this *Trie) StartsWith(prefix string) bool {
- node := this.SearchPrefix(prefix)
- return node != nil
-}
-
-func (this *Trie) SearchPrefix(s string) *Trie {
- node := this
- for _, c := range s {
- idx := c - 'a'
- if node.children[idx] == nil {
- return nil
- }
- node = node.children[idx]
- }
- return node
-}
-
-/**
- * Your Trie object will be instantiated and called as such:
- * obj := Constructor();
- * obj.Insert(word);
- * param_2 := obj.Search(word);
- * param_3 := obj.StartsWith(prefix);
- */
-```
-
-#### TypeScript
-
-```ts
-class TrieNode {
- children;
- isEnd;
- constructor() {
- this.children = new Array(26);
- this.isEnd = false;
- }
-}
-
-class Trie {
- root;
- constructor() {
- this.root = new TrieNode();
- }
-
- insert(word: string): void {
- let head = this.root;
- for (let char of word) {
- let index = char.charCodeAt(0) - 97;
- if (!head.children[index]) {
- head.children[index] = new TrieNode();
- }
- head = head.children[index];
- }
- head.isEnd = true;
- }
-
- search(word: string): boolean {
- let head = this.searchPrefix(word);
- return head != null && head.isEnd;
- }
-
- startsWith(prefix: string): boolean {
- return this.searchPrefix(prefix) != null;
- }
-
- private searchPrefix(prefix: string) {
- let head = this.root;
- for (let char of prefix) {
- let index = char.charCodeAt(0) - 97;
- if (!head.children[index]) return null;
- head = head.children[index];
- }
- return head;
- }
-}
-```
-
-#### Rust
-
-```rust
-use std::{cell::RefCell, collections::HashMap, rc::Rc};
-
-struct TrieNode {
- pub val: Option,
- pub flag: bool,
- pub child: HashMap>>,
-}
-
-impl TrieNode {
- fn new() -> Self {
- Self {
- val: None,
- flag: false,
- child: HashMap::new(),
- }
- }
-
- fn new_with_val(val: char) -> Self {
- Self {
- val: Some(val),
- flag: false,
- child: HashMap::new(),
- }
- }
-}
-
-struct Trie {
- root: Rc>,
-}
-
-/// Your Trie object will be instantiated and called as such:
-/// let obj = Trie::new();
-/// obj.insert(word);
-/// let ret_2: bool = obj.search(word);
-/// let ret_3: bool = obj.starts_with(prefix);
-impl Trie {
- fn new() -> Self {
- Self {
- root: Rc::new(RefCell::new(TrieNode::new())),
- }
- }
-
- fn insert(&self, word: String) {
- let char_vec: Vec = word.chars().collect();
- // Get the clone of current root node
- let mut root = Rc::clone(&self.root);
- for c in &char_vec {
- if !root.borrow().child.contains_key(c) {
- // We need to manually create the entry
- root.borrow_mut()
- .child
- .insert(*c, Rc::new(RefCell::new(TrieNode::new())));
- }
- // Get the child node
- let root_clone = Rc::clone(root.borrow().child.get(c).unwrap());
- root = root_clone;
- }
- {
- root.borrow_mut().flag = true;
- }
- }
-
- fn search(&self, word: String) -> bool {
- let char_vec: Vec = word.chars().collect();
- // Get the clone of current root node
- let mut root = Rc::clone(&self.root);
- for c in &char_vec {
- if !root.borrow().child.contains_key(c) {
- return false;
- }
- // Get the child node
- let root_clone = Rc::clone(root.borrow().child.get(c).unwrap());
- root = root_clone;
- }
- let flag = root.borrow().flag;
- flag
- }
-
- fn starts_with(&self, prefix: String) -> bool {
- let char_vec: Vec = prefix.chars().collect();
- // Get the clone of current root node
- let mut root = Rc::clone(&self.root);
- for c in &char_vec {
- if !root.borrow().child.contains_key(c) {
- return false;
- }
- // Get the child node
- let root_clone = Rc::clone(root.borrow().child.get(c).unwrap());
- root = root_clone;
- }
- true
- }
-}
-```
-
-#### JavaScript
-
-```js
-/**
- * Initialize your data structure here.
- */
-var Trie = function () {
- this.children = {};
-};
-
-/**
- * Inserts a word into the trie.
- * @param {string} word
- * @return {void}
- */
-Trie.prototype.insert = function (word) {
- let node = this.children;
- for (let char of word) {
- if (!node[char]) {
- node[char] = {};
- }
- node = node[char];
- }
- node.isEnd = true;
-};
-
-/**
- * Returns if the word is in the trie.
- * @param {string} word
- * @return {boolean}
- */
-Trie.prototype.search = function (word) {
- let node = this.searchPrefix(word);
- return node != undefined && node.isEnd != undefined;
-};
-
-Trie.prototype.searchPrefix = function (prefix) {
- let node = this.children;
- for (let char of prefix) {
- if (!node[char]) return false;
- node = node[char];
- }
- return node;
-};
-
-/**
- * Returns if there is any word in the trie that starts with the given prefix.
- * @param {string} prefix
- * @return {boolean}
- */
-Trie.prototype.startsWith = function (prefix) {
- return this.searchPrefix(prefix);
-};
-
-/**
- * Your Trie object will be instantiated and called as such:
- * var obj = new Trie()
- * obj.insert(word)
- * var param_2 = obj.search(word)
- * var param_3 = obj.startsWith(prefix)
- */
-```
-
-#### C#
-
-```cs
-public class Trie {
- bool isEnd;
- Trie[] children = new Trie[26];
-
- public Trie() {
-
- }
-
- public void Insert(string word) {
- Trie node = this;
- foreach (var c in word)
- {
- var idx = c - 'a';
- node.children[idx] ??= new Trie();
- node = node.children[idx];
- }
- node.isEnd = true;
- }
-
- public bool Search(string word) {
- Trie node = SearchPrefix(word);
- return node != null && node.isEnd;
- }
-
- public bool StartsWith(string prefix) {
- Trie node = SearchPrefix(prefix);
- return node != null;
- }
-
- private Trie SearchPrefix(string s) {
- Trie node = this;
- foreach (var c in s)
- {
- var idx = c - 'a';
- if (node.children[idx] == null)
- {
- return null;
- }
- node = node.children[idx];
- }
- return node;
- }
-}
-
-/**
- * Your Trie object will be instantiated and called as such:
- * Trie obj = new Trie();
- * obj.Insert(word);
- * bool param_2 = obj.Search(word);
- * bool param_3 = obj.StartsWith(prefix);
- */
-```
-