#include "transfer.h"
#include <bits/stdc++.h>
using namespace std;
vector<int> get_attachment(vector<int> source) {
int n = source.size(), x = 0;
vector<int> v;
for(int i = 0; i < n; i++){
x ^= source[i];
v.push_back(source[i]);
}
v.push_back(x);
return v;
}
vector<int> retrieve(vector<int> data) {
int n = data.size(); n/=2;
vector<int> og;
int x = 0, id = -1;
for(int i = 0; i < n; i++){
og.push_back(data[i]);
if(data[i] == data[i+n])x ^= data[i];
else id = i;
}
if(id != -1){
if(x == data.back())og[id] = 0;
else og[id] = 1;
}
return og;
}
