#include <bits/stdc++.h>
#include "game.h"
using namespace std;
// #define int int64_t
int N;
int done;
int remaining;
struct chefNode {
int chef;
set<pair<int, int>> connections;
};
vector<chefNode> chefs;
void initUnionfind(int n) {
chefs.clear();
chefs.resize(n);
for (int i = 0; i<n; i++) {
chefNode x;
x.chef = i;
for (int j = 0; j<n; j++) {
if (i == j) continue;
x.connections.insert({i, j});
}
chefs[i] = x;
}
}
int find(int x) {
if (chefs[x].chef == x) return x;
return chefs[x].chef = find(chefs[x].chef);
}
void unite(int a, int b) {
a = find(a); b = find(b);
if (a == b) return;
chefs[a].chef = b;
for (auto i: chefs[a].connections)
chefs[b].connections.insert(i);
chefs[a].connections.clear();
set<pair<int, int>> newConnections;
for (auto i: chefs[b].connections)
if (find(i.first) != find(i.second)) newConnections.insert(i);
chefs[b].connections = newConnections;
}
void initialize(int n) {
remaining = (n*(n-1))/2 +1;
done = 0;
N = n;
initUnionfind(n);
}
int hasEdge(int u, int v) {
remaining--;
if (find(u) == find(v)) return 0; // return rand()%2;
if (chefs[find(u)].connections.size() == 1 || chefs[find(v)].connections.size() == 1 || remaining+done < N) {
unite(find(u), find(v));
done++;
return 1;
}
chefs[find(u)].connections.erase({u, v});
chefs[find(v)].connections.erase({v, u});
return 0;
}
void test(int n) {
vector<pair<int, int>> edges;
for (int i = 0; i<n; i++) {
for (int j = i+1; j<n; j++) {
edges.push_back({i, j});
}
}
std::random_device rd;
std::mt19937 g(rd());
shuffle(edges.begin(), edges.end(), g);
initialize(n);
vector<int> answers;
for (auto i: edges) {
if (rand()%2==0) swap(i.first, i.second);
// cerr << i.first << " " << i.second << "\n";
answers.push_back(hasEdge(i.first, i.second));
}
assert(answers.back() == 1);
assert((int)accumulate(answers.begin(), answers.end(), 0) == (int)n-1);
}
// signed main() {
// while (true) {
// test(4);
// // cerr << "\n";
// }
// }
