xorTree.java

import java.util.Scanner;
import java.util.*;


class TrieNode {

    TrieNode children[];
    Hashtable<Integer, Integer> hijos;
    int index;
    int k;
    TrieNode(int m, int k){
        index=0;
        children=new TrieNode[m];
        hijos= new Hashtable<Integer, Integer>();
        this.k=k;
    }

    public void insert(int []a, int i) 
    { 
        if(i<a.length){
            if(this.hijos.containsKey(a[i])){
                int x=this.hijos.get(a[i]);
                this.children[x].insert(a, i+1);
            }else{
                hijos.put(a[i], index);
                children[index]=new TrieNode(this.children.length, a[i]);
                this.children[index].insert(a, i+1);
                index++;
            }
        }
    }

    public int nodes(){
        int ans=1;
        for(int i=0;i<index; i++){
            ans+=children[i].nodes();
        }
        return ans;
    }

    public String toString(){

        String ans= "("+String.valueOf(k)+" ";
        for(int i=0;i<index; i++){
            ans+=children[i].toString();
        }
        ans+=" )";
        return ans;
    }    
}


class xorTree{

    public static void main(String[] args) {
        Scanner in= new Scanner(System.in);

    }
}