結果
| 問題 |
No.3056 Disconnected Coloring
|
| コンテスト | |
| ユーザー |
 紙ぺーぱー
|
| 提出日時 | 2025-03-31 14:25:12 |
| 言語 | C#(csc) (csc 3.9.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 7,331 bytes |
| コンパイル時間 | 3,098 ms |
| コンパイル使用メモリ | 122,652 KB |
| 実行使用メモリ | 58,904 KB |
| 最終ジャッジ日時 | 2025-03-31 14:25:27 |
| 合計ジャッジ時間 | 13,837 ms |
|
ジャッジサーバーID （参考情報） |
judge5 / judge2 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 25 WA * 9 |
コンパイルメッセージ
Microsoft (R) Visual C# Compiler version 3.9.0-6.21124.20 (db94f4cc) Copyright (C) Microsoft Corporation. All rights reserved.
ソースコード
using System;
using System.Linq;
using System.Collections.Generic;
using Debug = System.Diagnostics.Trace;
using SB = System.Text.StringBuilder;
using static System.Math;
using static Program.IO.Scanner;
using Number = System.Int64;
using System.Numerics;
using C = System.Int64;
using V = System.Int64;
using System.ComponentModel;
#region IO
namespace Program.IO
{
using System.IO;
using System.Text;
using System.Globalization;
public class Printer : StreamWriter
{
public override IFormatProvider FormatProvider { get { return CultureInfo.InvariantCulture; } }
public Printer(Stream stream) : base(stream, new UTF8Encoding(false, true)) { }
}
static public class Scanner
{
public static StreamScanner sc = new StreamScanner(Console.OpenStandardInput());
public static int ri => sc.Integer();
public static long rl => sc.Long();
public static string rs => sc.Scan();
public static double rd => sc.Double();
}
public class StreamScanner
{
public StreamScanner(Stream stream) { str = stream; }
public readonly Stream str;
private readonly byte[] buf = new byte[1024];
private int len, ptr;
public bool isEof = false;
public bool IsEndOfStream { get { return isEof; } }
private byte read()
{
if (isEof) return 0;
if (ptr >= len)
{
ptr = 0;
if ((len = str.Read(buf, 0, 1024)) <= 0)
{
isEof = true;
return 0;
}
}
return buf[ptr++];
}
public char Char()
{
byte b = 0;
do b = read(); while ((b < 33 || 126 < b) && !isEof);
return (char)b;
}
public string Scan()
{
var sb = new StringBuilder();
for (var b = Char(); b >= 33 && b <= 126; b = (char)read()) sb.Append(b);
return sb.ToString();
}
public string ScanLine()
{
var sb = new StringBuilder();
for (var b = Char(); b != '\n' && b != 0; b = (char)read()) if (b != '\r') sb.Append(b);
return sb.ToString();
}
public long Long() { return isEof ? long.MinValue : long.Parse(Scan()); }
public int Integer() { return isEof ? int.MinValue : int.Parse(Scan()); }
public double Double() { return isEof ? double.NaN : double.Parse(Scan(), CultureInfo.InvariantCulture); }
}
}
#endregion
#region main
static class Ex
{
static public string AsString(this IEnumerable<char> ie) { return new string(ie.ToArray()); }
static public string AsJoinedString<T>(this IEnumerable<T> ie, string st = " ")
{
return string.Join(st, ie);
}
static public void Main()
{
Console.SetOut(new Program.IO.Printer(Console.OpenStandardOutput()) { AutoFlush = true });
var solver = new Program.Solver();
//*
var t = new System.Threading.Thread(solver.Solve, 50000000);
t.Start();
t.Join();
//*/
// solver.Solve();
Console.Out.Flush();
}
}
#endregion
namespace Program
{
public class Solver
{
public void Solve()
{
var n=ri;
var m=ri;
if(m%2!=0){
Console.WriteLine(-1);
return;
}
var f=new int[m];
var t=new int[m];
var cnt=Enumerate(n, x => new List<int>());
for (int i = 0; i < m; i++){
f[i]=ri-1;
t[i]=ri-1;
if(f[i]==0&&t[i]==n-1){
Console.WriteLine(-1);
return;
}
cnt[f[i]].Add(i);
cnt[t[i]].Add(i);
}
var ans=new char[m];
if(Max(cnt[0].Count,cnt[n-1].Count)*2>m){
var s=new DisjointSet(n);
for (int i = 0; i < m; i++){
ans[i]='R';
}
if(cnt[0].Count*2>m){
foreach(var x in cnt[0])ans[x]='B';
for (int i = 0; i < m; i++)if(ans[i]=='R')s.Unite(f[i],t[i]);
var e=cnt[0].Count-m;
foreach(var x in cnt[0]){
if(e==0)break;
if(!s.Same(n-1,t[x])){
e--;
ans[x]='R';
}
}
}else{
foreach(var x in cnt[n-1])ans[x]='B';
for (int i = 0; i < m; i++)if(ans[i]=='R')s.Unite(f[i],t[i]);
var e=cnt[n-1].Count-m;
foreach(var x in cnt[n-1]){
if(e==0)break;
if(!s.Same(0,f[x])){
e--;
ans[x]='R';
}
}
}
}else{
var used=new bool[m];
int r=0;int b=0;
foreach(var x in cnt[0]){ans[x]='R';used[x]=true;r++;}
foreach(var x in cnt[n-1]){ans[x]='B';used[x]=true;b++;}
for (int i = 0; i < m; i++)if(!used[i]){
if(r>b){ans[i]='B';b++;}
else {ans[i]='R';r++;}
}
}
Console.WriteLine(ans.AsString());
}
const long INF = 1L << 60;
static int[] dx = { -1, 0, 1, 0 };
static int[] dy = { 0, 1, 0, -1 };
/*
static IEnumerable<int> rep(int n) { for (int i = 0; i < n; i++) yield return i; }
static IEnumerable<(int, int)> rep(int n, int m)
{
for (int i = 0; i < n; i++)
for (int j = 0; j < m; j++) yield return (i, j);
}
*/
static T[] Enumerate<T>(int n, Func<int, T> f)
{
var a = new T[n]; for (int i = 0; i < a.Length; ++i) a[i] = f(i); return a;
}
static T[][] Enumerate<T>(int n, int m, Func<int, int, T> f)
{
return Enumerate(n, x => Enumerate(m, y => f(x, y)));
}
static T[][][] Enumerate<T>(int n, int m, int k, Func<int, int, int, T> f)
{
return Enumerate(n, x => Enumerate(m, k, (y, z) => f(x, y, z)));
}
static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }
}
}
#region Disjoint Set
public class DisjointSet {
int[] par;
byte[] rank;
public DisjointSet(int N) {
par = new int[N];
rank = new byte[N];
for (int i = 0; i < N; i++) { par[i] = -1; }
}
/// <summary>Find root of <c>id</c>. Time complexity: <c>O(α(N))</c></summary>
public int this[int id] {
get {
if ((par[id] < 0)) return id;
return par[id] = this[par[id]];
}
}
/// <summary>Unite <paramref name="x"/> and <paramref name="y"/>. Time complexity: <c>O(α(N))</c></summary>
public bool Unite(int x, int y) {
x = this[x]; y = this[y];
if (x == y) return false;
if (rank[x] < rank[y]) { var tmp = x; x = y; y = tmp; }
par[x] += par[y];
par[y] = x;
if (rank[x] == rank[y])
rank[x]++;
return true;
}
/// <summary>Size of <paramref name="x"/>. Time complexity: <c>O(α(N))</c></summary>
public int Size(int x) { return -par[this[x]]; }
public bool Same(int x, int y) { return this[x] == this[y]; }
}
#endregion