#include <fstream>
#define NMAX 100005
#define MAX_BITS 22

using namespace std;

ifstream cin("xormax.in");
ofstream cout("xormax.out");

int N, tempStart, ans, start = 1, stop = 1;
char bitSet[MAX_BITS];
int v[NMAX], xorSum[NMAX];

struct Trie
{
    int freq, start;
    Trie *fii[2];
};

Trie *trie = new Trie();

void Add(Trie *pos, char *bits)
{
    pos->freq++;

    if(*bits == '\0')
    {
        pos->start = tempStart;
        return ;
    }

    int bit = *bits - '0';

    if(pos->fii[bit]==NULL)
        pos->fii[bit] = new Trie();

    Add(pos->fii[bit], bits + 1);
}

int FindXor(Trie *pos, char *bits)
{
    if(*bits == '\0')
        return pos->start;

    int bit = *bits - '0';
    int otherBit = (bit + 1) % 2;

    if(pos->fii[otherBit] != NULL)
        return FindXor(pos->fii[otherBit], bits)
    else
        return FindXor(pos->fii[bit], bits + 1);

}

int main()
{

}