結果
| 問題 | No.2914 正閉路検出 |
| コンテスト | |
| ユーザー |
👑 |
| 提出日時 | 2026-07-02 23:22:01 |
| 言語 | C++17 (gcc 15.2.0 + boost 1.90.0) |
| 結果 |
TLE
|
| 実行時間 | - |
| コード長 | 6,387 bytes |
| 記録 | |
| コンパイル時間 | 3,046 ms |
| コンパイル使用メモリ | 224,972 KB |
| 実行使用メモリ | 6,528 KB |
| 最終ジャッジ日時 | 2026-07-02 23:22:13 |
| 合計ジャッジ時間 | 11,672 ms |
|
ジャッジサーバーID （参考情報） |
judge2_0 / judge1_0 |
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| ファイルパターン | 結果 |
|---|---|
| other | AC * 13 TLE * 1 -- * 41 |
ソースコード
#include <algorithm>
#include <atcoder/all>
#include <bitset>
#include <cassert>
#include <cmath>
#include <ctime>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using namespace atcoder;
typedef long long ll;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repr(i, n) for (int i = (int)(n) - 1; i >= 0; i--)
#define repk(i, k, n) for (int i = k; i < (int)(n); i++)
#define all(v) v.begin(), v.end()
#define mod1 1000000007
#define mod2 998244353
#define mod3 100000007
#define vi vector<int>
#define vs vector<string>
#define vc vector<char>
#define vl vector<ll>
#define vb vector<bool>
#define vvi vector<vector<int>>
#define vvc vector<vector<char>>
#define vvl vector<vector<ll>>
#define vvb vector<vector<bool>>
#define vvvi vector<vector<vector<int>>>
#define vvvl vector<vector<vector<ll>>>
#define pii pair<int, int>
#define pil pair<int, ll>
#define pli pair<ll, int>
#define pll pair<ll, ll>
#define vpii vector<pair<int, int>>
#define vpll vector<pair<ll, ll>>
#define vvpii vector<vector<pair<int, int>>>
#define vvpll vector<vector<pair<ll, ll>>>
template <typename T>
void debug(T e) {
cerr << e << endl;
}
template <typename T>
void debug(vector<T> &v) {
rep(i, v.size()) { cerr << v[i] << " "; }
cerr << endl;
}
template <typename T>
void debug(vector<vector<T>> &v) {
rep(i, v.size()) {
rep(j, v[i].size()) { cerr << v[i][j] << " "; }
cerr << endl;
}
}
template <typename T>
void debug(vector<pair<T, T>> &v) {
rep(i, v.size()) { cerr << v[i].first << " " << v[i].second << endl; }
}
template <typename T>
void debug(set<T> &st) {
for (auto itr = st.begin(); itr != st.end(); itr++) {
cerr << *itr << " ";
}
cerr << endl;
}
template <typename T>
void debug(multiset<T> &ms) {
for (auto itr = ms.begin(); itr != ms.end(); itr++) {
cerr << *itr << " ";
}
cerr << endl;
}
template <typename T>
void debug(map<T, T> &mp) {
for (auto itr = mp.begin(); itr != mp.end(); itr++) {
cerr << itr->first << " " << itr->second << endl;
}
}
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
cerr << H << " ";
debug_out(T...);
}
using mint = modint998244353;
void debug_mint1(vector<mint> &vec) {
for (int i = 0; i < vec.size(); i++) {
cerr << vec[i].val() << " ";
}
cerr << endl;
}
void debug_mint2(vector<vector<mint>> &vec) {
for (int i = 0; i < vec.size(); i++) {
for (int j = 0; j < vec[i].size(); j++) {
cerr << vec[i][j].val() << " ";
}
cerr << endl;
}
}
// ポテンシャル付 Union-Find
// https://qiita.com/drken/items/cce6fc5c579051e64fab#%E9%87%8D%E3%81%BF%E3%81%A4%E3%81%8D-unionfind-%E6%9C%A8%E3%81%AE%E5%87%A6%E7%90%86
struct UnionFind {
vector<int> par;
vector<int> rank;
vector<ll> diff_weight;
UnionFind(int n = 1, ll SUM_UNITY = 0) { init(n, SUM_UNITY); }
void init(int n = 1, ll SUM_UNITY = 0) {
par.resize(n);
rank.resize(n);
diff_weight.resize(n);
for (int i = 0; i < n; ++i)
par[i] = i, rank[i] = 0, diff_weight[i] = SUM_UNITY;
}
int root(int x) {
if (par[x] == x) {
return x;
} else {
int r = root(par[x]);
diff_weight[x] += diff_weight[par[x]];
return par[x] = r;
}
}
ll weight(int x) {
root(x);
return diff_weight[x];
}
bool issame(int x, int y) { return root(x) == root(y); }
bool merge(int x, int y, ll w) {
w += weight(x);
w -= weight(y);
x = root(x);
y = root(y);
if (x == y) return false;
if (rank[x] < rank[y]) swap(x, y), w = -w;
if (rank[x] == rank[y]) ++rank[x];
par[y] = x;
diff_weight[y] = w;
return true;
}
ll diff(int x, int y) { return weight(y) - weight(x); }
};
ll INF = 1000000000023LL;
vector<ll> find_route(vector<vector<pll>> &graph, ll start, ll goal){
queue<ll> que;
que.push(start);
ll N = graph.size();
vector<ll> dist(N, INF);
dist[start] = 0;
while (que.size()){
ll p = que.front();
que.pop();
for (pll x: graph[p]){
if (dist[x.first] < INF) continue;
dist[x.first] = dist[p] + 1;
}
}
vector<ll> vec;
ll now = goal;
while (true){
if (now == start) break;
for (pll x: graph[now]){
if (dist[x.first] < dist[now]){
vec.push_back(x.second);
now = x.first;
}
}
}
reverse(all(vec));
return vec;
}
int main() {
ll N, M;
cin >> N >> M;
vector<ll> u(M);
vector<ll> v(M);
vector<ll> w(M);
for (ll i = 0; i < M; i++){
cin >> u[i] >> v[i] >> w[i];
u[i]--;
v[i]--;
}
UnionFind tree(N);
vector<vector<pll>> graph(N, vector<pll>(0));
for (ll i = 0; i < M; i++){
if (!tree.issame(u[i], v[i])){
tree.merge(u[i], v[i], w[i]);
graph[u[i]].push_back(make_pair(v[i], i));
graph[v[i]].push_back(make_pair(u[i], i));
}
else if (tree.diff(u[i], v[i]) == w[i]){
continue;
}
else if (tree.diff(u[i], v[i]) < w[i]){
vector<ll> route = find_route(graph, v[i], u[i]);
route.push_back(i);
ll L = route.size();
cout << L << endl;
cout << v[i] + 1 << endl;
for (ll i = 0; i < L; i++){
cout << route[i] + 1;
if (i < L - 1) cout << " ";
}
cout << endl;
return 0;
}
else{
vector<ll> route = find_route(graph, u[i], v[i]);
route.push_back(i);
ll L = route.size();
cout << L << endl;
cout << u[i] + 1 << endl;
for (ll i = 0; i < L; i++){
cout << route[i] + 1;
if (i < L - 1) cout << " ";
}
cout << endl;
return 0;
}
}
cout << -1 << endl;
}