結果
| 問題 | No.1640 簡単な色塗り |
| コンテスト | |
| ユーザー |
C
|
| 提出日時 | 2026-10-23 14:51:59 |
| 言語 | C++23(gcc16) (gcc 16.2.0 + boost 1.92.0 + ACL) |
| 結果 |
AC
不安定
|
| 実行時間 | 44 ms / 2,000 ms |
| + 0µs | |
| コード長 | 5,918 bytes |
| 記録 | |
| コンパイル時間 | 8,054 ms |
| コンパイル使用メモリ | 402,752 KB |
| 実行使用メモリ | 28,148 KB |
| 最終ジャッジ日時 | 2026-10-23 14:52:21 |
| 合計ジャッジ時間 | 20,009 ms |
|
ジャッジサーバーID (参考情報) |
judge1_0 / judge4_0 |
(要ログイン)
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 53 |
ソースコード
#include <bits/stdc++.h>
#include <atcoder/all>
#include <boost/polygon/point_data.hpp>
#include <boost/polygon/voronoi.hpp>
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(x) begin(x),end(x)
#define sz(x) (int)(x).size()
using namespace std;
using namespace atcoder;
using ll=long long;
using ld=long double;
using vll=vector<ll>;
using vvll=vector<vll>;
using vi=vector<int>;
using vvi=vector<vi>;
using pll=pair<ll,ll>;
using pi=pair<int,int>;
// using mint=modint998244353;
// using mint2=static_modint<2>;
// using BoostPoint=boost::polygon::point_data<int>;
// using Voronoi=boost::polygon::voronoi_diagram<double>;
#line 2 "graph/others/eulerian-trail.hpp"
#include <algorithm>
#include <cstdlib>
#include <iterator>
#include <stack>
#include <utility>
#include <vector>
#line 2 "structure/union-find/union-find.hpp"
#line 4 "structure/union-find/union-find.hpp"
#include <cstddef>
#line 7 "structure/union-find/union-find.hpp"
struct UnionFind {
std::vector<int> data;
UnionFind() = default;
explicit UnionFind(std::size_t sz) : data(sz, -1) {}
bool unite(int x, int y) {
x = find(x), y = find(y);
if (x == y) return false;
if (data[x] > data[y]) std::swap(x, y);
data[x] += data[y];
data[y] = x;
return true;
}
int find(int k) {
if (data[k] < 0) return (k);
return data[k] = find(data[k]);
}
int size(int k) { return -data[find(k)]; }
bool same(int x, int y) { return find(x) == find(y); }
std::vector<std::vector<int>> groups() {
int n = (int)data.size();
std::vector<std::vector<int>> ret(n);
for (int i = 0; i < n; i++) {
ret[find(i)].emplace_back(i);
}
ret.erase(
std::remove_if(ret.begin(), ret.end(),
[&](const std::vector<int>& v) { return v.empty(); }),
ret.end());
return ret;
}
};
#line 11 "graph/others/eulerian-trail.hpp"
/**
* @brief Eulerian Trail(オイラー路)
*
*/
template <bool directed>
struct EulerianTrail {
std::vector<std::vector<std::pair<int, int> > > g;
std::vector<std::pair<int, int> > es;
int M;
std::vector<int> used_vertex, used_edge, deg;
explicit EulerianTrail(int V) : g(V), M(0), used_vertex(V), deg(V) {}
void add_edge(int a, int b) {
es.emplace_back(a, b);
g[a].emplace_back(b, M);
if (directed) {
deg[a]++;
deg[b]--;
} else {
g[b].emplace_back(a, M);
deg[a]++;
deg[b]++;
}
M++;
}
std::pair<int, int> get_edge(int idx) const { return es[idx]; }
std::vector<std::vector<int> > enumerate_eulerian_trail() {
if (directed) {
for (auto& p : deg)
if (p != 0) return {};
} else {
for (auto& p : deg)
if (p & 1) return {};
}
used_edge.assign(M, 0);
std::vector<std::vector<int> > ret;
for (int i = 0; i < (int)g.size(); i++) {
if (g[i].empty() || used_vertex[i]) continue;
ret.emplace_back(go(i));
}
return ret;
}
std::vector<std::vector<int> > enumerate_semi_eulerian_trail() {
UnionFind uf(g.size());
for (auto& p : es) uf.unite(p.first, p.second);
std::vector<std::vector<int> > group(g.size());
for (int i = 0; i < (int)g.size(); i++) group[uf.find(i)].emplace_back(i);
std::vector<std::vector<int> > ret;
used_edge.assign(M, 0);
for (auto& vs : group) {
if (vs.empty()) continue;
int latte = -1, malta = -1;
if (directed) {
for (auto& p : vs) {
if (std::abs(deg[p]) > 1) {
return {};
} else if (deg[p] == 1) {
if (latte >= 0) return {};
latte = p;
}
}
} else {
for (auto& p : vs) {
if (deg[p] & 1) {
if (latte == -1)
latte = p;
else if (malta == -1)
malta = p;
else
return {};
}
}
}
ret.emplace_back(go(latte == -1 ? vs.front() : latte));
if (ret.back().empty()) ret.pop_back();
}
return ret;
}
std::vector<int> go(int s) {
std::stack<std::pair<int, int> > st;
std::vector<int> ord;
st.emplace(s, -1);
while (!st.empty()) {
int idx = st.top().first;
used_vertex[idx] = true;
if (g[idx].empty()) {
ord.emplace_back(st.top().second);
st.pop();
} else {
auto e = g[idx].back();
g[idx].pop_back();
if (used_edge[e.second]) continue;
used_edge[e.second] = true;
st.emplace(e);
}
}
ord.pop_back();
std::reverse(ord.begin(), ord.end());
return ord;
}
};
int main()
{
ios::sync_with_stdio(false);
cin.tie(nullptr);
int N;
cin>>N;
vi a(N),b(N),ans(N,-1),rev(N,-1),deg(N,0);
vvi g(N);
rep(i,0,N){
cin>>a[i]>>b[i];
a[i]--,b[i]--;
if(a[i]==b[i]){
ans[i]=a[i];
rev[a[i]]=i;
continue;
}
g[a[i]].push_back(i);
g[b[i]].push_back(i);
deg[a[i]]++,deg[b[i]]++;
}
queue<int>q;
rep(i,0,N){
if(deg[i]==1)q.push(i);
}
while(!q.empty()){
int ball=q.front();
q.pop();
if(deg[ball]==0||rev[ball]!=-1)continue;
for(auto op:g[ball]){
if(ans[op]==-1){
ans[op]=ball;
rev[ball]=op;
int other=(ball==a[op])?b[op]:a[op];
if(deg[other]>0){
deg[other]--;
if(deg[other]==1)q.push(other);
}
break;
}
}
deg[ball]=0;
}
int remainL=0,remainR=0;
bool deg0=false;
rep(i,0,N){
if(ans[i]==-1)remainR++;
if(rev[i]==-1){
remainL++;
if(deg[i]==0)deg0=true;
}
}
if(remainL!=remainR||deg0){
cout<<"No\n";
return 0;
}
EulerianTrail<false>et(2*N);
rep(op,0,N){
if(ans[op]!=-1)continue;
et.add_edge(a[op],op+N);
et.add_edge(b[op],op+N);
}
for(auto& tour:et.enumerate_eulerian_trail()){
for(int j=0;j<sz(tour);j+=2){
auto [ball,op]=et.get_edge(tour[j]);
ans[op-N]=ball;
}
}
cout<<"Yes\n";
rep(op,0,N){
cout<<ans[op]+1<<'\n';
}
}
C