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

int n;

int inter(int i, int j){
    if (i == j) return 0;
    assert(i < j);
    cout << i+1 << " " << j+1 << endl;
    int v; cin >> v;
    if (v == -1) exit(0);
    return v;
}
void swp(deque<int> &a, int c, int f, int t){
    if (c == 0) return;
    for (int &p: a){
        if (p == f){
            p = t;
        }
        else if (p == t){
            p = f;
        }
    }
}
void recurse(int begin, int end){
    if (begin+1 == end) return;

    int mid = (begin + end)>>1;
    recurse(begin, mid);
    recurse(mid, end);
    if (inter(mid-1, mid) == 0) return;

    deque<int> x, y;
    for (int i=begin; i<mid-1; i++) x.push_back(i);
    x.push_back(mid);

    y.push_back(mid-1);
    for (int i=mid+1; i<end; i++) y.push_back(i);

    for (int i=begin; i<end; i++){
        if (x[0] > y[0]) swap(x, y);
        if (x.size() == 0){
            int u = inter(i, y[0]);
            swp(y, u, i, y[0]);
            y.pop_front();
        }
        else if (y.size() == 0){
            int u = inter(i, x[0]);
            swp(x, u, i, x[0]);
            x.pop_front();
        }
        else{
            int posl = x[0], posr = y[0];
            int v = inter(posl, posr);
            swp(x, v, posl, posr);
            swp(y, v, posl, posr);

            int u = inter(i, posl);
            swp(x, u, i, posl);
            swp(y, u, i, posl);

            if (v == 0){
                x.pop_front();
            }
            else{
                y.pop_front();
            }
        }
    }
}

signed main(){
    cin.tie(0)->sync_with_stdio(0);
    cin >> n;
    recurse(0, n);

    cout << "-1 -1" << endl;
}