#include <bits/stdc++.h>
#ifndef ALEXPC
#include "interactive.h"
#endif
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#define FOR(i,a) for (int i=0;i<(a);++i)
#define FORD(i,a) for (int i=(a)-1;i>=0;i--)
#define FORT(i,a,b) for (int i=(a);i<=(b);++i)
#define FORTD(i,b,a) for (int i=(b);i>=(a);--i)
#define trav(i,v) for (auto i : v)
#define all(v) v.begin(),v.end()
#define ad push_back
#define fr first
#define sc second
#define mpr(a,b) make_pair(a,b)
#define pir pair<int,int>
#define make_unique(v) v.erase(unique(all(v)),v.end())
#define fastio ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define srng mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
#define y1 EsiHancagorcRepa
#ifdef ALEXPC
int ask(int position);
std::vector<int> get_pairwise_xor(std::vector<int> positions);
#endif
map<int,int> qan;
vector<int> guess(int n){
vector<int> ans(n);
ans[0]=ask(1);
FOR(i,7){
vector<int> tv;
FORT(j,1,n-1){
if ((1<<i)&j){
tv.ad(j+1);
}
}
if (tv.size()==0)continue;
vector<int> gt=get_pairwise_xor(tv);
trav(k,gt){
qan[k^ans[0]]-=(1<<i);
}
qan[ans[0]]-=(1<<i);
tv.ad(1);
gt=get_pairwise_xor(tv);
trav(k,gt){
qan[k^ans[0]]+=(1<<i);
}
}
//cout<<qan[2]<<" "<<qan[4]<<endl;
trav(tv,qan){
if (tv.sc==0)continue;
ans[tv.sc/2]=tv.fr;
//cerr<<tv.sc<<" "<<tv.fr<<endl;
}
return ans;
}
#ifdef ALEXPC
namespace {
const int MAX_VALUE_OF_N = 100;
const int MAX_VALUE_OF_Q = 200;
int numberOfQueries = 0;
int n;
std::vector<int> a;
void wrong_answer(const char *MSG) {
printf("-1\n");
exit(0);
}
}
void query() {
numberOfQueries++;
if (numberOfQueries > MAX_VALUE_OF_Q) {
wrong_answer("Number of queries exceeded");
}
}
int ask(int position) {
query();
if (position < 1 || position > n) {
wrong_answer("Not correct position");
}
return a[position - 1];
}
vector<int> get_pairwise_xor(vector<int> positions) {
query();
if (positions.empty() || positions.size() > n) {
wrong_answer("Not correct size");
}
sort(positions.begin(), positions.end());
for (int i = 1; i < positions.size(); i++) {
if (positions[i] == positions[i - 1]) {
wrong_answer("Not unique");
}
}
for (int i = 0; i < positions.size(); i++) {
if (positions[i] < 1 || positions[i] > n) {
wrong_answer("Not correct position");
}
}
vector<int> pairwise_xor;
for (int i = 0; i < positions.size(); i++) {
for (int j = 0; j < positions.size(); j++) {
pairwise_xor.push_back(a[positions[i] - 1] ^ a[positions[j] - 1]);
}
}
sort(pairwise_xor.begin(), pairwise_xor.end());
return pairwise_xor;
}
vector<int> guess(int n);
int main() {
assert(scanf("%d", &n) == 1);
assert(1 <= n && n <= MAX_VALUE_OF_N);
for (int i = 1; i <= n; i++) {
int x;
assert(scanf("%d", &x) == 1);
assert(x >= 0 && x <= 1000 * 1000 * 1000);
a.push_back(x);
}
vector<int> participant_solution = guess(n);
if (participant_solution.size() != n) {
wrong_answer("-1");
}
printf("%d\n", n);
for (auto i: participant_solution) {
printf("%d ", i);
}
printf("\n");
printf("%d\n", numberOfQueries);
return 0;
}
#endif
