Descripción del título
Implementar Trie (árbol de prefijos)
Código AC
class Trie {
class Node{
boolean is_end;
Node[] son=new Node[26];
}
Node root;
/** Initialize your data structure here. */
public Trie() {
root=new Node();
}
/** Inserts a word into the trie. */
public void insert(String word) {
Node p=root;
char[] ch=word.toCharArray();
for(char item:ch){
int k=item-'a';
if(p.son[k]==null)
p.son[k]=new Node();
p=p.son[k];
}
p.is_end=true;
}
/** Returns if the word is in the trie. */
public boolean search(String word) {
Node p=root;
char[] ch=word.toCharArray();
for(char item:ch){
int k=item-'a';
if(p.son[k]==null) return false;
p=p.son[k];
}
return p.is_end;
}
/** Returns if there is any word in the trie that starts with the given prefix. */
public boolean startsWith(String prefix) {
Node p=root;
char[] ch=prefix.toCharArray();
for(char item:ch){
int k=item-'a';
if(p.son[k]==null) return false;
p=p.son[k];
}
return true;
}
}
/**
* 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);
*/
