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#include <vector>
#include <numeric>
#include <algorithm>
#include <set>
#include <cmath>
#include <random>
#include <chrono>
using namespace std;
static mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
static bool adj[45][45];
static vector<int> adj_list[45];
static int N_glob, M_glob;
struct Candidate {
vector<int> row;
int score;
};
inline bool is_adj_or_same(int u, int v) {
if (u == v) return true;
return adj[u][v];
}
std::vector<std::vector<int>> create_map(int N, int M,
std::vector<int> A, std::vector<int> B) {
N_glob = N;
M_glob = M;
for(int i=1; i<=N; ++i) {
for(int j=1; j<=N; ++j) adj[i][j] = false;
adj_list[i].clear();
}
for(int i=0; i<M; ++i) {
int u = A[i];
int v = B[i];
adj[u][v] = adj[v][u] = true;
adj_list[u].push_back(v);
adj_list[v].push_back(u);
}
int lower_bound_K = ceil(sqrt(M/2.0));
int node_bound = ceil(sqrt(N));
int start_W = max({lower_bound_K, node_bound, 1});
if (start_W < 2 && N > 1) start_W = 2;
auto start_time = chrono::steady_clock::now();
for (int W = start_W; W <= 240; ++W) {
for (int attempt = 0; attempt < 5; ++attempt) {
if (chrono::duration_cast<chrono::milliseconds>(chrono::steady_clock::now() - start_time).count() > 1900) {
// Time limit approaching, stop trying
break;
}
vector<vector<int>> grid;
set<pair<int,int>> covered_edges;
set<int> covered_nodes;
bool possible = true;
for (int r = 0; r < 240; ++r) {
if (covered_edges.size() == M && covered_nodes.size() == N) {
int H = grid.size();
int K = max(W, H);
vector<vector<int>> final_map(K, vector<int>(K));
for(int i=0; i<K; ++i) {
const vector<int>& src_row = (i < H) ? grid[i] : grid[H-1];
for(int j=0; j<K; ++j) {
final_map[i][j] = (j < W) ? src_row[j] : src_row[W-1];
}
}
return final_map;
}
if (r >= 240) { possible = false; break; }
int beam_width = 40;
vector<Candidate> beam;
beam.push_back({{}, 0});
for (int c = 0; c < W; ++c) {
vector<Candidate> next_beam;
int up_node = (r > 0) ? grid[r-1][c] : -1;
for (const auto& cand : beam) {
int left_node = (c > 0) ? cand.row.back() : -1;
vector<int> possibilities;
auto check_and_add = [&](int v) {
if (up_node != -1 && !is_adj_or_same(v, up_node)) return;
possibilities.push_back(v);
};
if (left_node != -1) {
check_and_add(left_node);
for(int v : adj_list[left_node]) check_and_add(v);
} else if (up_node != -1) {
check_and_add(up_node);
for(int v : adj_list[up_node]) check_and_add(v);
} else {
// Random start
for(int k=0; k<10; ++k) {
possibilities.push_back((rng() % N) + 1);
}
}
if (possibilities.empty()) continue;
sort(possibilities.begin(), possibilities.end());
possibilities.erase(unique(possibilities.begin(), possibilities.end()), possibilities.end());
shuffle(possibilities.begin(), possibilities.end(), rng);
if (possibilities.size() > 8) possibilities.resize(8);
for (int v : possibilities) {
int score = cand.score;
if (covered_nodes.find(v) == covered_nodes.end()) score += 5000;
if (left_node != -1 && left_node != v) {
int mn = min(left_node, v), mx = max(left_node, v);
if (covered_edges.find({mn, mx}) == covered_edges.end()) score += 100;
}
if (up_node != -1 && up_node != v) {
int mn = min(up_node, v), mx = max(up_node, v);
if (covered_edges.find({mn, mx}) == covered_edges.end()) score += 100;
}
Candidate next = cand;
next.row.push_back(v);
next.score = score;
next_beam.push_back(next);
}
}
if (next_beam.empty()) {
beam.clear();
break;
}
sort(next_beam.begin(), next_beam.end(), [](const Candidate& a, const Candidate& b){
return a.score > b.score;
});
if (next_beam.size() > beam_width) next_beam.resize(beam_width);
beam = next_beam;
}
if (beam.empty()) {
possible = false;
break;
}
const auto& best_row = beam[0].row;
grid.push_back(best_row);
for (int c = 0; c < W; ++c) {
int v = best_row[c];
covered_nodes.insert(v);
if (c > 0) {
int u = best_row[c-1];
if (u != v) covered_edges.insert({min(u,v), max(u,v)});
}
if (r > 0) {
int u = grid[r-1][c];
if (u != v) covered_edges.insert({min(u,v), max(u,v)});
}
}
}
}
}
return {};
}