#include "longesttrip.h"
#include <bits/stdc++.h>
using namespace std;
#define ll int
#define sz(x) (ll)x.size()
#define F first
#define S second
#define endl "\n"
#define pb push_back
typedef vector <ll> vi;
typedef pair <ll,ll> ii;
typedef vector <ii> vii;
#define dbg(x) cout<<#x<<": "<<x<<endl;
#define dbg2(x,y) cout<<#x<<": "<<x<<" "<<#y<<": "<<y<<endl;
#define dbg3(x,y,z) cout<<#x<<": "<<x<<" "<<#y<<": "<<y<<" "<<#z<<": "<<z<<endl;
void printVct(const vi &v){
for (ll i =0; i<sz(v); i++)
cout<<v[i]<<" ";
cout<<endl;
}
vi longest_trip(int n, int d){
vi st1, st2;
st1.pb(0);
st2.pb(1);
//create stacks
for (ll i = 2; i<n; i++){
ll x = are_connected({st1.back()}, {i});
ll y = are_connected({st2.back()}, {i});
if (x){
st1.pb(i);
}
else if (y){
st2.pb(i);
}
else{
for (ll j = 0; j<sz(st1); j++){
st2.pb(st1[j]);
}
st1.assign(1, i);
}
}
// cout<<"st1: ";
// printVct(st1);
// cout<<"st2: ";
// printVct(st2);
//merge stacks if possible
if (are_connected({st1[0]}, {st2.back()})){
vi ans;
for (ll i = 0; i<sz(st2); i++) ans.pb(st2[i]);
for (ll i = 0; i<sz(st1); i++) ans.pb(st1[i]);
return ans;
}
else if (are_connected({st1.back()}, {st2[0]})){
vi ans;
for (ll i = 0; i<sz(st1); i++) ans.pb(st1[i]);
for (ll i = 0; i<sz(st2); i++) ans.pb(st2[i]);
return ans;
}
// cout<<"CHECK 0"<<endl;
//search for first connnection between stacks
ll firstConnectionStart = 1;
while ((firstConnectionStart < sz(st1)-1) && !are_connected({st1[firstConnectionStart]}, st2)){
firstConnectionStart++;
}
// dbg(firstConnectionStart);
if (firstConnectionStart >= sz(st1) - 1){ //no connection case => 2 strongly/fully connected stacks
// cout<<"CHECK 2"<<endl;
if (sz(st1) > sz(st2)){
return st1;
}
else{
return st2;
}
}
ll firstConnectionEnd = 1;
while (!are_connected({st2[firstConnectionEnd]}, {firstConnectionStart})){
firstConnectionEnd++;
}
// dbg(firstConnectionEnd);
// cout<<"CHECK 1"<<endl;
// return vi();
vi ans;
for (ll i = firstConnectionStart+1; i<sz(st1); i++){
ans.pb(st1[i]);
}
for (ll i = 0; i<=firstConnectionStart; i++){
ans.pb(st1[i]);
}
for (ll i = firstConnectionEnd; i<sz(st2); i++){
ans.pb(st2[i]);
}
for (ll i =0; i<firstConnectionEnd; i++){
ans.pb(st2[i]);
}
return ans;
}
/*
2
5 1
1
1 1
0 0 1
0 0 0 1
4 1
1
0 0
0 0 1
5
1 0 2 3 4
4
2
0 1
3
4
*/
