leetcode 208. Implement Trie (Prefix Tree)

Implement a trie with 

insert

, 

search

,
and 

startsWith

 methods.

Note:

You may assume that all inputs are consist of lowercase letters 

a-z

.

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public class Trie {
private class node{
boolean mark;
char val;
node(char mchar){
val=mchar;
}
node[] children=new node[26];
}
private node root;
public Trie() {
root = new node(' ');
}

public void insert(String word) {
node temp=root;
for(int i=0;i<word.length();i++){
char mchar=word.charAt(i);
if(temp.children[mchar-'a']==null){
temp.children[mchar-'a']=new node(mchar);
}
temp=temp.children[mchar-'a'];
}
temp.mark=true;
}

public boolean search(String word) {
node temp=root;
for(int i=0;i<word.length();i++){
char mchar=word.charAt(i);
if(temp.children[mchar-'a']==null){
return false;
}
temp=temp.children[mchar-'a'];
}
return  temp.mark;
}

public boolean startsWith(String prefix) {
node temp=root;
for(int i=0;i<prefix.length();i++){
char mchar=prefix.charAt(i);
if(temp.children[mchar-'a']==null){
return false;
}
temp=temp.children[mchar-'a'];
}
return  true;
}

}