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.
classTrie:def__init__(self):self.children=[None]*26self.is_end=Falsedefinsert(self,word:str)->None:node=selfforcinword:idx=ord(c)-ord('a')ifnode.children[idx]isNone:node.children[idx]=Trie()node=node.children[idx]node.is_end=Truedefsearch(self,word:str)->bool:node=self._search_prefix(word)returnnodeisnotNoneandnode.is_enddefstartsWith(self,prefix:str)->bool:node=self._search_prefix(prefix)returnnodeisnotNonedef_search_prefix(self,prefix:str):node=selfforcinprefix:idx=ord(c)-ord('a')ifnode.children[idx]isNone:returnNonenode=node.children[idx]returnnode# 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)
classTrie{privateTrie[]children;privatebooleanisEnd;publicTrie(){children=newTrie[26];}publicvoidinsert(Stringword){Trienode=this;for(charc:word.toCharArray()){intidx=c-'a';if(node.children[idx]==null){node.children[idx]=newTrie();}node=node.children[idx];}node.isEnd=true;}publicbooleansearch(Stringword){Trienode=searchPrefix(word);returnnode!=null&&node.isEnd;}publicbooleanstartsWith(Stringprefix){Trienode=searchPrefix(prefix);returnnode!=null;}privateTriesearchPrefix(Strings){Trienode=this;for(charc:s.toCharArray()){intidx=c-'a';if(node.children[idx]==null){returnnull;}node=node.children[idx];}returnnode;}}/** * 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); */
classTrie{private:vector<Trie*>children;boolisEnd;Trie*searchPrefix(strings){Trie*node=this;for(charc:s){intidx=c-'a';if(!node->children[idx])returnnullptr;node=node->children[idx];}returnnode;}public:Trie():children(26),isEnd(false){}voidinsert(stringword){Trie*node=this;for(charc:word){intidx=c-'a';if(!node->children[idx])node->children[idx]=newTrie();node=node->children[idx];}node->isEnd=true;}boolsearch(stringword){Trie*node=searchPrefix(word);returnnode!=nullptr&&node->isEnd;}boolstartsWith(stringprefix){Trie*node=searchPrefix(prefix);returnnode!=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); */
typeTriestruct{children[26]*TrieisEndbool}funcConstructor()Trie{returnTrie{}}func(this*Trie)Insert(wordstring){node:=thisfor_,c:=rangeword{idx:=c-'a'ifnode.children[idx]==nil{node.children[idx]=&Trie{}}node=node.children[idx]}node.isEnd=true}func(this*Trie)Search(wordstring)bool{node:=this.SearchPrefix(word)returnnode!=nil&&node.isEnd}func(this*Trie)StartsWith(prefixstring)bool{node:=this.SearchPrefix(prefix)returnnode!=nil}func(this*Trie)SearchPrefix(sstring)*Trie{node:=thisfor_,c:=ranges{idx:=c-'a'ifnode.children[idx]==nil{returnnil}node=node.children[idx]}returnnode}/** * 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); */
usestd::{cell::RefCell,collections::HashMap,rc::Rc};structTrieNode{pubval:Option<char>,pubflag:bool,pubchild:HashMap<char,Rc<RefCell<TrieNode>>>,}implTrieNode{fnnew()->Self{Self{val:None,flag:false,child:HashMap::new(),}}fnnew_with_val(val:char)->Self{Self{val:Some(val),flag:false,child:HashMap::new(),}}}structTrie{root:Rc<RefCell<TrieNode>>,}/// 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);implTrie{fnnew()->Self{Self{root:Rc::new(RefCell::new(TrieNode::new())),}}fninsert(&self,word:String){letchar_vec:Vec<char>=word.chars().collect();// Get the clone of current root nodeletmutroot=Rc::clone(&self.root);forcin&char_vec{if!root.borrow().child.contains_key(c){// We need to manually create the entryroot.borrow_mut().child.insert(*c,Rc::new(RefCell::new(TrieNode::new())));}// Get the child nodeletroot_clone=Rc::clone(root.borrow().child.get(c).unwrap());root=root_clone;}{root.borrow_mut().flag=true;}}fnsearch(&self,word:String)->bool{letchar_vec:Vec<char>=word.chars().collect();// Get the clone of current root nodeletmutroot=Rc::clone(&self.root);forcin&char_vec{if!root.borrow().child.contains_key(c){returnfalse;}// Get the child nodeletroot_clone=Rc::clone(root.borrow().child.get(c).unwrap());root=root_clone;}letflag=root.borrow().flag;flag}fnstarts_with(&self,prefix:String)->bool{letchar_vec:Vec<char>=prefix.chars().collect();// Get the clone of current root nodeletmutroot=Rc::clone(&self.root);forcin&char_vec{if!root.borrow().child.contains_key(c){returnfalse;}// Get the child nodeletroot_clone=Rc::clone(root.borrow().child.get(c).unwrap());root=root_clone;}true}}
/** * Initialize your data structure here. */varTrie=function(){this.children={};};/** * Inserts a word into the trie. * @param {string} word * @return {void} */Trie.prototype.insert=function(word){letnode=this.children;for(letcharofword){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){letnode=this.searchPrefix(word);returnnode!=undefined&&node.isEnd!=undefined;};Trie.prototype.searchPrefix=function(prefix){letnode=this.children;for(letcharofprefix){if(!node[char])returnfalse;node=node[char];}returnnode;};/** * 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){returnthis.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) */
publicclassTrie{boolisEnd;Trie[]children=newTrie[26];publicTrie(){}publicvoidInsert(stringword){Trienode=this;foreach(varcinword){varidx=c-'a';node.children[idx]??=newTrie();node=node.children[idx];}node.isEnd=true;}publicboolSearch(stringword){Trienode=SearchPrefix(word);returnnode!=null&&node.isEnd;}publicboolStartsWith(stringprefix){Trienode=SearchPrefix(prefix);returnnode!=null;}privateTrieSearchPrefix(strings){Trienode=this;foreach(varcins){varidx=c-'a';if(node.children[idx]==null){returnnull;}node=node.children[idx];}returnnode;}}/** * 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); */