#include <bits/stdc++.h>
#include "doll.h"
using namespace std;
#define SIZE(x) (int)x.size()
#define forn(i,n) for(int i=0;i<int(n);i++)
#define forsn(i,s,n) for(int i=int(s);i<int(n);i++)
#define pb push_back
typedef vector<int> vi;
vi L, R, v, state;
int t, skip, s;
void build(int u, int l, int r) {
L.pb(0), R.pb(0), v.pb(0);
if(r-l<=skip) {
v[u]=-1, skip-=r-l;
return;
}
if(r-l==1) return;
v[u]=--s;
int m=(l+r)/2;
build(L[u]=t++,l,m);
build(R[u]=t++,m,r);
}
void dfs(int u, int a) {
if(u&&v[u]==-1) dfs(0,a);
else if(!v[u]) v[u]=a;
else if(state[u]^=1) dfs(L[u],a);
else dfs(R[u],a);
}
void create_circuit(int m, vi a) {
vi c(m+1), x, y;
c[0]=a[0];
int n=SIZE(a),sz=1;
if(n==1) return answer(c,x,y);
forsn(i,1,m+1) c[i]=-1;
while(sz<n) sz*=2;
skip=sz-n;
build(t++,0,sz);
a.pb(0),state.assign(t,0);
forsn(i,1,n+1) dfs(0,a[i]);
forn(i,t) if(L[i]||R[i]) x.pb(v[L[i]]),y.pb(v[R[i]]);
answer(c,x,y);
}
