#include "doll.h"
#include <bits/stdc++.h>
#define fr first
#define sc second
#define pii pair<int, int>
using namespace std;
int N, M, S;
vector <int> A, C, X, Y;
// A - sequance
// C - edges of triggers
// X/Y - edges of switches
// M - triggers vertexes
void solve() {
vector <vector<int>> after(M + 1);
vector <int> cnt(M + 1, 0);
A.push_back(0);
for (int i = 1; i <= N; i++) {
after[A[i]].push_back(A[i + 1]);
cnt[A[i]]++;
}
int id = -1;
for (int i = 1; i <= M; i++) {
if (cnt[i] == 0) {
continue;
}
if (cnt[i] == 1) {
C[i] = after[i][0];
}
if (cnt[i] == 2) {
C[i] = id--;
X.push_back(after[i][0]);
Y.push_back(after[i][1]);
}
if (cnt[i] == 3) {
}
if (cnt[i] == 4) {
}
}
}
//3 6
//1 3 2 2 1 3
void create_circuit(int MM, vector<int> AA) {
M = MM;
N = AA.size();
A.resize(N + 1);
A[0] = 0;
for (int i = 0; i < N; i++) {
A[i + 1] = AA[i];
}
C.resize(M + 1);
solve();
C[0] = A[1];
answer(C, X, Y);
}
