造福后人，虽然我仍然 wrong answer on test 23。

gen:

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

const int N = 100010;

mt19937 rng(time(NULL));

int n = 20, q = 20;
int fa[N];

int main() {
    cout << n << " " << q << endl;
    for (int i = 2; i <= n; i++) {
        fa[i] = rng() % (i - 1) + 1;
        if (rng() % 2) {
            cout << i << " " << fa[i] << endl;
        } else {
            cout << fa[i] << " " << i << endl;
        }
    }
    vector<pair<int, int> > path;
    for (int i = 1; i <= q; i++) {
        int opt = rng() % 4;
        while (opt > 1 && path.empty()) { opt = rng() % 4; }
        if (opt == 0) { opt = 1; }
        cout << opt << " ";
        if (opt == 1) {
            int x = rng() % n + 1, y = rng() % n + 1;
            if (x > y) { swap(x, y); }
            cout << x << " " << y << endl;
            path.push_back(make_pair(x, y));
        } else if (opt == 2) {
            swap(path[rng() % path.size()], path[path.size() - 1]);
            cout << path.back().first << " " << path.back().second << endl;
            path.pop_back();
        } else {
            int d = rng() % 2;
            cout << d << endl;
        }
    }
}

check:

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



int main() {
    while (true) {
        system("CF1464Fgen.exe > CF1464F.in");
        system("CF1464F2.exe < CF1464F.in > CF1464F.out");
        system("CF1464Fsol.exe < CF1464F.in > CF1464F.ans");
        if (system("fc CF1464F.out CF1464F.ans /W")) {
            system("pause");
            return 0;
        }
    }
}