#include"longesttrip.h"
#include<bits/stdc++.h>
#define For(i,a,b) for(int i=(a);i<=(b);++i)
using namespace std;
#define pb push_back
typedef vector<int>vi;

int n;
int mp[260][260];

int Q(int i,int j){
	if(mp[i][j]!=-1)return mp[i][j];
	return mp[i][j]=mp[j][i]=are_connected({i},{j});
}
int Q(vi a,vi b){
	if(a.size()==1 && b.size()==1) return Q(a[0],b[0]);
	return are_connected(a,b);
}
void operator +=(vi&a,vi&b){
	for(int x:b) a.pb(x);
}
vi longest_trip(int N,int D)
{
	n=N;
	if(n==1)return {0};
	For(i,0,n-1)For(j,0,n-1)mp[i][j]=(i==j?0:-1);
	vi a,b;
	a.pb(0),b.pb(1);
	auto add1=[&](int i){
		if(Q(i,a.back())) a.pb(i);
		else if(Q(i,b.back())) b.pb(i);
		else reverse(b.begin(),b.end()),a+=b,b.clear(),b.pb(i);
	};
	auto add2=[&](int i,int j){
		if(Q(i,j)){
			add1(i),add1(j);
		}else{
			if(Q(i,a.back())) a.pb(i),add1(j);
			else a.pb(j),add1(i);
		}
	};
	for(int i=2;i<n;){
		if(i+1<n) add2(i,i+1),i+=2;
		else add1(i),i+=1;
	}
	
	if(!b.size())return a;
	if(!Q(a,b))return a.size()>b.size()?a:b;
	if(Q(a[0],b[0])) return reverse(a.begin(),a.end()),a+=b,a;
	if(Q(a.back(),b[0])) return a+=b,a;
	if(Q(a[0],b.back())) return b+=a,b;
	if(Q(a.back(),b.back())) return reverse(a.begin(),a.end()),b+=a,b;
	
	vi aa=a,bb=b;
	while(a.size()>1){
		int mid=a.size()>>1; vi al,ar;
		For(i,0,mid-1) al.pb(a[i]);
		For(i,mid,a.size()-1) ar.pb(a[i]);
		if(Q(al,b)) a=al;
		else a=ar;
	}
	while(b.size()>1){
		int mid=b.size()>>1; vi bl,br;
		For(i,0,mid-1) bl.pb(b[i]);
		For(i,mid,b.size()-1) br.pb(b[i]);
		if(Q(bl,a)) b=bl;
		else b=br;
	}
	int u=a[0],v=b[0];
	a=aa,b=bb;
	For(i,0,(int)a.size()-1) if(a[i]==u)
		For(j,0,(int)b.size()-1) if(b[j]==v){
			rotate(a.begin(),a.begin()+i+1,a.end());
			rotate(b.begin(),b.begin()+j,b.end());
			return a+=b,a;
		}
}