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

#define REP(i, n) for (int i = 0; i < n; i++)
#define REPR(i, n) for (int i = n; i >= 0; i--)
#define FOR(i, m, n) for (ll i = m; i < n; i++)
#define FORR(i, m, n) for (ll i = m; i >= n; i--)
#define REPO(i, n) for (ll i = 1; i <= n; i++)
#define ll long long
#define INF (ll)1ll << 60
#define MINF (-1 * INF)
#define ALL(n) n.begin(), n.end()
#define MOD (ll)1000000007
#define P pair<ll, ll>
int n, x = 0;

int main(){
  cin >> n;
  vector<int> s(n);
  REP(i, n) {
    cin >> s[i];
    x ^= s[i];
  }
  if(x == 0){
    cout << 0 << endl;
    ll a, b;
    cin >> a >> b;
    a--;
    x ^= s[a];
    s[a] -= b;
    x ^= s[a];
    cin >> a;
    if(a == -1)return 0;
  }
  else cout << 1 << endl;
  while(1){
    REP(i, n){
      if(s[i] == 0)continue;
      if((x ^ s[i]) < s[i]){
        cout << i + 1 << " " << s[i] - (x ^ s[i]) << endl;
        s[i] = (x ^ s[i]);
        x = 0;
        break;
      }
    }
    ll a, b;
    cin >> a;
    if(a == -1)return 0;
    cin >> a >> b;
    a--;
    x ^= s[a];
    s[a] -= b;
    x ^= s[a];
    cin >> a;
    if(a == -1)return 0;
  }
}