#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;

#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define rep(i, n) for (int i = 0; i < (n); i += 1)
#define len(a) ((int)(a).size())

mt19937 rnd(234);
const ll inf = 1e18;
int cnt = 0;

int query(int i, int j) {
    if (i == j)
        return 0;
    cout << i + 1 << " " << j + 1 << endl;
    ++cnt;
    assert(cnt <= 25000);
    int res;
    cin >> res;
    if (res == 0) {
        exit(0);
    }
    return res;
}

int32_t main() {
    if (0) {
        ios::sync_with_stdio(0);
        cin.tie(0);
        cout.tie(0);
    }

    int n;
    cin >> n;

    vector<int> check(n);
    for (int i = 0; i < n; ++i)
        check[i] = i;
    shuffle(all(check), rnd);

    check.resize(min(int(check.size()), 24999 / n));

    map<vector<int>, int> st;
    for (int i = 0; i < n; ++i) {
        vector<int> dists;
        for (auto c : check) {
            int dist = query(i, c);
            dists.push_back(dist);
        }
        if (st.count(dists)) {
            query(st[dists], i);
        }
        st[dists] = i;
    }
    assert(false);

    return 0;
}