#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
using namespace std;

string ten_to_2(int val, int need_size) {
    string s;
    while(val > 0) {
        s.push_back((val % 2) + '0');
        val /= 2;
    }
    for(int i = (int)s.size(); i < need_size; i++) {
        s.push_back('0');
    }
    return s;
}

bool smaller2(int first, int second, int n){
    string f = ten_to_2(first, n);
    string s = ten_to_2(second, n);
    for(int i = 0; i < n; i++) {
        if(f[i] == s[i]) {
            continue;
        }
        if(f[i] < s[i]) {
            return true;
        } else {
            return false;
        }
    }
}

int main() {
    int n; cin >> n;
    vector<int>f((1 << n));
    for(int i = 0; i < (1 << n); i++) {
        string s; cin >> s;
        cin >> f[i];
    }
    vector<int>a((1 << n));
    for(int i = 0; i < (1 << n); i++) {
        int val = f[i];
        for(int j = 0; j < i; j++) {
            if(smaller2(j, i, n)) {
                val = val ^ f[j];
            }
        }
        a[i] = val;
    }
    for(int i = 0; i < (1 << n); i++) {
        string ans = ten_to_2(i, n);
        reverse(ans.begin(), ans.end());
        cout << ans << " " << a[i] << endl;
    }
}