69 lines
1.4 KiB
Rust
69 lines
1.4 KiB
Rust
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use std::collections::HashMap;
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#[derive(Debug)]
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pub struct TrieNode {
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is_word: bool,
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children: HashMap<char, TrieNode>,
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}
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#[derive(Debug)]
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pub enum TrieResult {
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Failed,
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Prefix,
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Exists,
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}
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impl TrieNode {
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pub fn contains(&self, key: &str) -> (TrieResult, &TrieNode) {
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if key.is_empty() {
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return (TrieResult::Failed, self);
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}
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let mut current = self;
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for c in key.chars() {
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match current.children.get(&c) {
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Some(node) => current = node,
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None => return (TrieResult::Failed, current),
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}
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}
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if current.is_word {
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(TrieResult::Exists, current)
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} else {
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(TrieResult::Prefix, current)
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}
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}
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}
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#[derive(Debug)]
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pub struct Trie {
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pub root: TrieNode,
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}
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impl Trie {
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pub fn new() -> Self {
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Trie {
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root: TrieNode {
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is_word: false,
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children: HashMap::new(),
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},
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}
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}
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pub fn add<'a, I>(&mut self, keys: I)
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where
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I: Iterator<Item = &'a String>,
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{
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for key in keys {
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let mut current = &mut self.root;
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for c in key.chars() {
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current = current.children.entry(c).or_insert(TrieNode {
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is_word: false,
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children: HashMap::new(),
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});
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}
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current.is_word = true;
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}
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}
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}
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