#line 1 "library/Template/template.hpp"
#include <bits/stdc++.h>
using namespace std;

#define rep(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define ALL(v) (v).begin(),(v).end()
using ll=long long int;
const int inf = 0x3fffffff;
const ll INF = 0x1fffffffffffffff;
template<typename T>inline bool chmax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
template<typename T>inline bool chmin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
#line 2 "sol.cpp"
// #include "Utility/fastio.hpp"

using P=pair<int,int>;


// FastIO io;
int main(){
    int n,tmp;
    cin>>n;
    vector<int> a(n);
    rep(i,0,n)cin>>a[i];

    int gr=0;
    ll sum=0;
    set<int> bit[20];

    auto process=[&](int k,int x){
        sum-=x;
        gr^=a[k];
        rep(j,0,30)if(a[k]>>j&1)bit[j].erase(k);
        a[k]-=x;
        gr^=a[k];
        rep(j,0,30)if(a[k]>>j&1)bit[j].insert(k);
    };
    auto out=[&](int k,int x,bool done=0)->void{
        cout<<k+1<<' '<<x<<endl;
        cin>>tmp;
        if(done)assert(tmp==-1);
        else assert(tmp==0);
    };
    auto in=[&]()->P{
        int k,x;
        cin>>k>>x;
        k--;
        cin>>tmp;
        assert(tmp==0);
        return {k,x};
    };

    
    rep(i,0,n){
        gr^=a[i];
        sum+=a[i];
        rep(j,0,20)if(a[i]>>j&1)bit[j].insert(i);
    }
    if(gr==0){
        cout<<0<<endl;
        auto [k,x]=in();
        process(k,x);
    }
    else cout<<1<<endl;
    
    for(;;){
        assert(gr!=0);
        int sel=-1;
        for(int j=29;j>=0;j--){
            if(gr>>j&1){
                assert(bit[j].size());
                sel=*bit[j].begin();
                break;
            }
        }
        assert(sel!=-1);
        int x=a[sel]-a[sel]^gr;
        process(sel,x);
        out(sel,x,sum==0);
        if(sum==0)break;

        auto [k,y]=in();
        process(k,y);
    }
    return 0;
}