#include <bits/stdc++.h>
using namespace std;

int msb(int v){
    if(v == 0)return -1;
    int res = 0;
    while(v >> res)res++;
    res--;
    return res;
}

int main(){
    //ios::sync_with_stdio(false);
    //cin.tie(0);
    int n, v = 0, p, x, s;
    cin >> n;
    vector<int> a(n);
    set<pair<int,int>> S;
    for(int i = 0; i < n; i++){
        cin >> a[i];
        v ^= a[i];
        S.insert({a[i], i});
    }
    auto update = [&](int p, int x){
        S.erase(make_pair(a[p], p));
        v ^= a[p];
        a[p] -= x;
        v ^= a[p];
        S.insert(make_pair(a[p], p));
    };
    auto my_turn = [&](){
        int v2 = 1 << msb(v);
        auto it = S.rbegin();
        int p = it -> second;
        if((v ^ a[p]) > a[p]){
            auto it = S.lower_bound(make_pair(v2, -1));
            p = it -> second;
        }
        cout << p + 1 << " " << a[p] - (v ^ a[p]) << endl;
        update(p, a[p] - (v ^ a[p]));
    };
    if(v == 0){
        cout << 0 << endl;
        cin >> p >> x;
        update(--p, x);
    }else{
        cout << 1 << endl;
        my_turn();
    }
    while(true){
        cin >> s;
        if(s == -1)break;
        my_turn();
        cin >> s;
        if(s == -1)break;
        cin >> p >> x;
        update(--p, x);
    }
}