Function main

CSES/Intro/TowerH.cc:19–29

}

int main(){
	ios_base::sync_with_stdio(false),cin.tie(nullptr);

    int n; cin >> n;
    cout << solve(n) << endl;
    for (auto i : ans) {
        cout << i.first << " " << i.second << endl;
    }
    cout << endl;
	return 0;
}