#include "longesttrip.h" #include <bits/stdc++.h> using namespace std; #define pb push_back #define mp make_pair #define pii pair<int, int> #define fi first #define se second map<vector<int>, map<vector<int>, int> > mmm; int query(vector<int> a, vector<int> b){ if (b.size()==2&&b.back()==b[b.size()-2])b.pop_back(); if (!mmm[a][b]&&!mmm[b][a])mmm[b][a]=mmm[a][b]=are_connected(a, b)+1; return mmm[a][b]-1; } int queryd(deque<int> aa, deque<int> bb){ vector<int> a, b; for (auto c:aa)a.pb(c); for (auto c:bb)b.pb(c); if (b.size()==2&&b.back()==b[b.size()-2])b.pop_back(); if (!mmm[a][b]&&!mmm[b][a])mmm[b][a]=mmm[a][b]=are_connected(a, b)+1; return mmm[a][b]-1; } vector<int> longest_trip(int n, int d){ mmm.clear(); if (d==3){ vector<int> ans; for (int i=0; i<n; ++i)ans.pb(i); return ans; } if (d==2){ deque<int> ans(1, 0); int done=1; if (are_connected({0}, {1}))ans.pb(1); else ans.pb(2), done=2; for (int i=1; i<n; ++i)if (i!=done){ if (are_connected({i}, {ans.back()}))ans.pb(i); else ans.push_front(i); } vector<int> res; for (auto a:ans)res.pb(a); return res; } vector<int> ord; for (int i=0; i<n; ++i)ord.pb(i); mt19937 rng(67); shuffle(ord.begin(), ord.end(), rng); deque<int> a(1, ord[0]), b(1, ord[1]); bool prevb=0; for (int j=2; j<n; ++j){ int i=ord[j]; if (!prevb){ if (query({i}, {a.back()}))a.pb(i), prevb=0; else if (query({i}, {b.back()}))b.pb(i), prevb=1; else{ prevb=0; if (j+1<n){ if (query({i}, {ord[j+1]})){ while (b.size())a.pb(b.back()), b.pop_back(); b.pb(i); b.pb(ord[j+1]); } else{ a.pb(ord[j+1]); while (b.size())a.pb(b.back()), b.pop_back(); b.pb(i); } ++j; } else{ while (b.size())a.pb(b.back()), b.pop_back(); b.pb(i); } } } else{ if (query({i}, {a.back()}))a.pb(i), prevb=0; else b.pb(i), prevb=1; } } if (b.size()>a.size())swap(a, b); if (!queryd(a, b)){ vector<int> res; for (auto c:a)res.pb(c); return res; } if (!query({a[0], a.back()}, {b[0], b.back()})){ int low=-1, high=a.size()-1; while (low+1<high){ int mid=(low+high)/2; deque<int> temp; for (int i=low+1; i<=mid; ++i)temp.pb(a[i]); if (queryd(temp, b))high=mid; else low=mid; } int froma=high; low=-1, high=b.size()-1; while (low+1<high){ int mid=(low+high)/2; vector<int> temp; for (int i=low+1; i<=mid; ++i)temp.pb(b[i]); if (query({a[froma]}, temp))high=mid; else low=mid; } vector<int> res; for (int p=0; p<a.size(); ++p)res.pb(a[(p+froma+1)%a.size()]); for (int p=0; p<b.size(); ++p)res.pb(b[(p+high)%b.size()]); return res; } if (query({a.back()}, {b.back()})){ while (b.size())a.pb(b.back()), b.pop_back(); } else if (query({a.back()}, {b[0]})){ for (auto c:b)a.pb(c); } else if (query({a[0]}, {b.back()})){ while (b.size())a.push_front(b.back()), b.pop_back(); } else if (query({a[0]}, {b[0]})){ for (auto c:b)a.push_front(c); } vector<int> res; for (auto c:a)res.pb(c); return res; }