結果
| 問題 | No.2337 Equidistant |
| ユーザー |
 KumaTachiRen
|
| 提出日時 | 2023-06-02 21:54:22 |
| 言語 | C# (.NET 8.0.203) |
| 結果 |
AC
|
| 実行時間 | 2,404 ms / 4,000 ms |
| コード長 | 21,045 bytes |
| コンパイル時間 | 7,641 ms |
| コンパイル使用メモリ | 142,872 KB |
| 実行使用メモリ | 345,144 KB |
| 最終ジャッジ日時 | 2023-08-28 03:20:26 |
| 合計ジャッジ時間 | 39,128 ms |
|
ジャッジサーバーID （参考情報） |
judge11 / judge14 |
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テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | AC | 69 ms
26,192 KB |
| testcase_01 | AC | 70 ms
28,144 KB |
| testcase_02 | AC | 69 ms
26,176 KB |
| testcase_03 | AC | 71 ms
26,208 KB |
| testcase_04 | AC | 69 ms
26,300 KB |
| testcase_05 | AC | 69 ms
26,104 KB |
| testcase_06 | AC | 75 ms
27,712 KB |
| testcase_07 | AC | 76 ms
29,920 KB |
| testcase_08 | AC | 76 ms
27,880 KB |
| testcase_09 | AC | 75 ms
27,732 KB |
| testcase_10 | AC | 75 ms
27,636 KB |
| testcase_11 | AC | 1,422 ms
190,296 KB |
| testcase_12 | AC | 1,404 ms
192,560 KB |
| testcase_13 | AC | 1,398 ms
188,656 KB |
| testcase_14 | AC | 1,390 ms
188,288 KB |
| testcase_15 | AC | 1,384 ms
190,340 KB |
| testcase_16 | AC | 1,399 ms
190,456 KB |
| testcase_17 | AC | 1,371 ms
192,360 KB |
| testcase_18 | AC | 1,376 ms
190,272 KB |
| testcase_19 | AC | 1,371 ms
190,216 KB |
| testcase_20 | AC | 1,349 ms
190,420 KB |
| testcase_21 | AC | 1,386 ms
187,008 KB |
| testcase_22 | AC | 1,193 ms
204,156 KB |
| testcase_23 | AC | 1,195 ms
202,032 KB |
| testcase_24 | AC | 2,005 ms
182,048 KB |
| testcase_25 | AC | 1,248 ms
202,156 KB |
| testcase_26 | AC | 2,404 ms
182,412 KB |
| testcase_27 | AC | 1,357 ms
209,624 KB |
| testcase_28 | AC | 1,350 ms
345,144 KB |
コンパイルメッセージ
Determining projects to restore... Restored /home/judge/data/code/main.csproj (in 120 ms). .NET 向け Microsoft (R) Build Engine バージョン 17.0.0-preview-21470-01+cb055d28f Copyright (C) Microsoft Corporation.All rights reserved. プレビュー版の .NET を使用しています。https://aka.ms/dotnet-core-preview をご覧ください main -> /home/judge/data/code/bin/Release/net6.0/main.dll main -> /home/judge/data/code/bin/Release/net6.0/publish/
ソースコード
using System;
using System.ComponentModel;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.Contracts;
using System.IO;
using System.Linq;
using System.Numerics;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Text;
using static Functions;
using ModInt = StaticModInt<Mod998244353>;
static class Program
{
static public void Main(string[] args)
{
Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });
new Solver();
Console.Out.Flush();
}
}
public class Solver
{
public Solver()
{
Solve();
}
struct Op : IReRootingDPOperator<int, int>
{
public int SIdentity => 0;
public int TtoS(int t) => t;
public int Merge(int x, int y) => x + y;
public int AddRoot(int i, int j, int x) => x + 1;
}
void Solve()
{
int n = ri, q = ri;
var g = new Graph(n);
var dp = new ReRootingDP<int, int, Op>(n);
for (int i = 0; i < n - 1; i++)
{
int a = ri - 1, b = ri - 1;
g.AddEdge(a, b);
dp.AddEdge(a, b);
}
var td = new TreeDoubling(g);
var tj = new TreeJump(g);
dp.Calc();
var ans = new List<int>();
for (int i = 0; i < q; i++)
{
int s = ri - 1, t = ri - 1;
var dist = td.Dist(s, t);
if (dist % 2 == 1)
{
ans.Add(0);
}
else
{
int c = n;
int m = tj.Jump(s, t, (int)dist / 2);
c -= dp[tj.Jump(m, s, 1), m];
c -= dp[tj.Jump(m, t, 1), m];
ans.Add(c);
}
}
WriteJoin("\n", ans);
}
const long INF = 1L << 60;
int ri { get { return (int)sc.Integer(); } }
long rl { get { return sc.Integer(); } }
ulong rul { get { return sc.UInteger(); } }
double rd { get { return sc.Double(); } }
string rs { get { return sc.Scan(); } }
string rline { get { return sc.Line(); } }
public StreamScanner sc = new StreamScanner(Console.OpenStandardInput());
[MethodImpl(MethodImplOptions.AggressiveInlining)]
T[] RepArray<T>(T t, int count) => Enumerable.Repeat(t, count).ToArray();
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void WriteJoin<T>(string s, IEnumerable<T> t) => Console.WriteLine(string.Join(s, t));
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void WriteMat<T>(T[,] a)
{
int sz1 = a.GetLength(0);
int sz2 = a.GetLength(1);
for (int i = 0; i < sz1; i++)
{
var s = new List<string>();
for (int j = 0; j < sz2; j++) s.Add(a[i, j].ToString());
WriteJoin(" ", s);
}
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Write(object t) => Console.WriteLine(t.ToString());
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Write(string str) => Console.WriteLine(str);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Write(string str, object arg1) => Console.WriteLine(str, arg1);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Write(string str, object arg1, object arg2) => Console.WriteLine(str, arg1, arg2);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Write(string str, object arg1, object arg2, object arg3) => Console.WriteLine(str, arg1, arg2, arg3);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Write(string str, params object[] arg) => Console.WriteLine(str, arg);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void WriteFlush(object t)
{ Console.WriteLine(t.ToString()); Console.Out.Flush(); }
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void WriteError(object t) => Console.Error.WriteLine(t.ToString());
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void YN(bool t) => Console.WriteLine(t ? "YES" : "NO");
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void Yn(bool t) => Console.WriteLine(t ? "Yes" : "No");
[MethodImpl(MethodImplOptions.AggressiveInlining)]
void yn(bool t) => Console.WriteLine(t ? "yes" : "no");
}
public interface IStaticMod
{
uint Mod { get; }
bool IsPrime { get; }
}
public readonly struct Mod1000000007 : IStaticMod
{
public uint Mod => 1000000007;
public bool IsPrime => true;
}
public readonly struct Mod998244353 : IStaticMod
{
public uint Mod => 998244353;
public bool IsPrime => true;
}
public readonly struct StaticModInt<T> : IEquatable<StaticModInt<T>>, IFormattable where T : struct, IStaticMod
{
internal readonly uint _v;
private static readonly T op = default;
public int Value => (int)_v;
public static int Mod => (int)op.Mod;
public static StaticModInt<T> Zero => default;
public static StaticModInt<T> One => new StaticModInt<T>(1u);
[MethodImpl(256)]
public static StaticModInt<T> Raw(int v)
{
var u = unchecked((uint)v);
return new StaticModInt<T>(u);
}
[MethodImpl(256)]
public StaticModInt(long v) : this(Round(v)) { }
[MethodImpl(256)]
public StaticModInt(ulong v) : this((uint)(v % op.Mod)) { }
[MethodImpl(256)]
private StaticModInt(uint v) => _v = v;
[MethodImpl(256)]
private static uint Round(long v)
{
var x = v % op.Mod;
if (x < 0) x += op.Mod;
return (uint)x;
}
[MethodImpl(256)]
public static StaticModInt<T> operator ++(StaticModInt<T> v)
{
var x = v._v + 1;
if (x == op.Mod) x = 0;
return new StaticModInt<T>(x);
}
[MethodImpl(256)]
public static StaticModInt<T> operator --(StaticModInt<T> v)
{
var x = v._v;
if (x == 0) x = op.Mod;
return new StaticModInt<T>(x - 1);
}
[MethodImpl(256)]
public static StaticModInt<T> operator +(StaticModInt<T> lhs, StaticModInt<T> rhs)
{
var v = lhs._v + rhs._v;
if (v >= op.Mod) v -= op.Mod;
return new StaticModInt<T>(v);
}
[MethodImpl(256)]
public static StaticModInt<T> operator -(StaticModInt<T> lhs, StaticModInt<T> rhs)
{
unchecked
{
var v = lhs._v - rhs._v;
if (v >= op.Mod) v += op.Mod;
return new StaticModInt<T>(v);
}
}
[MethodImpl(256)]
public static StaticModInt<T> operator *(StaticModInt<T> lhs, StaticModInt<T> rhs) => new StaticModInt<T>((uint)((ulong)lhs._v * rhs._v % op.Mod));
[MethodImpl(256)]
public static StaticModInt<T> operator /(StaticModInt<T> lhs, StaticModInt<T> rhs) => lhs * rhs.Inv();
[MethodImpl(256)]
public static StaticModInt<T> operator +(StaticModInt<T> v) => v;
[MethodImpl(256)]
public static StaticModInt<T> operator -(StaticModInt<T> v) => new StaticModInt<T>(v._v == 0 ? 0 : op.Mod - v._v);
[MethodImpl(256)]
public static bool operator ==(StaticModInt<T> lhs, StaticModInt<T> rhs) => lhs._v == rhs._v;
[MethodImpl(256)]
public static bool operator !=(StaticModInt<T> lhs, StaticModInt<T> rhs) => lhs._v != rhs._v;
[MethodImpl(256)]
public static implicit operator StaticModInt<T>(int v) => new StaticModInt<T>(v);
[MethodImpl(256)]
public static implicit operator StaticModInt<T>(uint v) => new StaticModInt<T>((long)v);
[MethodImpl(256)]
public static implicit operator StaticModInt<T>(long v) => new StaticModInt<T>(v);
[MethodImpl(256)]
public static implicit operator StaticModInt<T>(ulong v) => new StaticModInt<T>(v);
[MethodImpl(256)]
public static implicit operator long(StaticModInt<T> v) => v._v;
[MethodImpl(256)]
public static implicit operator ulong(StaticModInt<T> v) => v._v;
[MethodImpl(256)]
public StaticModInt<T> Pow(long n)
{
var x = this;
var r = new StaticModInt<T>(1U);
while (n > 0)
{
if ((n & 1) > 0) r *= x;
x *= x;
n >>= 1;
}
return r;
}
[MethodImpl(256)]
public StaticModInt<T> Inv()
{
var (x, y, g) = ExtGcd(_v, op.Mod);
return new StaticModInt<T>(x);
}
[MethodImpl(256)]
static (long x, long y, long g) ExtGcd(long a, long b)
{
if (b == 0) return a >= 0 ? (1, 0, a) : (-1, 0, -a);
long c = SafeMod(a, b);
var (x2, y2, g) = ExtGcd(b, c);
long x = SafeMod(y2, b);
long y = (g - a * x) / b;
return (x, y, g);
}
[MethodImpl(256)]
static long SafeMod(long x, long m)
{
long r = x % m;
if (r < 0) r += m;
return r;
}
[MethodImpl(256)]
public override string ToString() => _v.ToString();
[MethodImpl(256)]
public string ToString(string format, IFormatProvider formatProvider) => _v.ToString(format, formatProvider);
[MethodImpl(256)]
public override bool Equals(object obj) => obj is StaticModInt<T> m && Equals(m);
[MethodImpl(256)]
public bool Equals(StaticModInt<T> other) => _v == other._v;
[MethodImpl(256)]
public override int GetHashCode() => _v.GetHashCode();
}
public static class Functions
{
public static int Popcount(ulong x)
{
x = (x & 0x5555555555555555UL) + ((x >> 1) & 0x5555555555555555UL);
x = (x & 0x3333333333333333UL) + ((x >> 2) & 0x3333333333333333UL);
x = (x & 0x0f0f0f0f0f0f0f0fUL) + ((x >> 4) & 0x0f0f0f0f0f0f0f0fUL);
x = (x & 0x00ff00ff00ff00ffUL) + ((x >> 8) & 0x00ff00ff00ff00ffUL);
x = (x & 0x0000ffff0000ffffUL) + ((x >> 16) & 0x0000ffff0000ffffUL);
x = (x & 0x00000000ffffffffUL) + ((x >> 32) & 0x00000000ffffffffUL);
return (int)x;
}
public static int Popcount(int x)
{
x = (x & 0x55555555) + ((x >> 1) & 0x55555555);
x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
x = (x & 0x0f0f0f0f) + ((x >> 4) & 0x0f0f0f0f);
x = (x & 0x00ff00ff) + ((x >> 8) & 0x00ff00ff);
x = (x & 0x0000ffff) + ((x >> 16) & 0x0000ffff);
return x;
}
public static int Ctz(long x)
{
if (x == 0) return -1;
return Popcount((ulong)((x & -x) - 1));
}
public static int SafeMod(int x, int m)
{
int r = x % m;
return r < 0 ? r + m : r;
}
public static long SafeMod(long x, long m)
{
long r = x % m;
return r < 0 ? r + m : r;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static int Sign(long x) => x == 0 ? 0 : (x < 0 ? -1 : 1);
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static int DigitSum(long n, int d = 10) { long s = 0; while (n > 0) { s += n % d; n /= d; } return (int)s; }
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static long Floor(long a, long b) => a >= 0 ? a / b : (a + 1) / b - 1;
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static long Ceil(long a, long b) => a > 0 ? (a - 1) / b + 1 : a / b;
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static int Gcd(int a, int b) => b == 0 ? a : Gcd(b, a % b);
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static long Gcd(long a, long b) => b == 0 ? a : Gcd(b, a % b);
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static void Swap(ref int x, ref int y) { x ^= y; y ^= x; x ^= y; }
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static void Swap(ref long x, ref long y) { x ^= y; y ^= x; x ^= y; }
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static void Swap<T>(ref T x, ref T y) { T t = y; y = x; x = t; }
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static T Clamp<T>(T x, T l, T r) where T : IComparable<T> => x.CompareTo(l) <= 0 ? l : (x.CompareTo(r) <= 0 ? x : r);
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static T Clamp<T>(ref T x, T l, T r) where T : IComparable<T> => x = x.CompareTo(l) <= 0 ? l : (x.CompareTo(r) <= 0 ? x : r);
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static void Chmin<T>(ref T x, T y) where T : IComparable<T> { if (x.CompareTo(y) > 0) x = y; }
[MethodImpl(MethodImplOptions.AggressiveInlining)] public static void Chmax<T>(ref T x, T y) where T : IComparable<T> { if (x.CompareTo(y) < 0) x = y; }
public static int LowerBound<T>(T[] arr, Func<T, int> comp, int l = -1, int r = -1) => LowerBound<T>(arr.AsSpan<T>(), comp, l, r);
public static int LowerBound<T>(Span<T> data, Func<T, int> comp, int l = -1, int r = -1)
{
if (data.Length == 0) return -1;
if (l == -1) l = 0;
if (r == -1) r = data.Length;
while (l < r)
{
int x = (l + r) / 2;
if (comp(data[x]) < 0) l = x + 1;
else r = x;
}
return l;
}
}
public class StreamScanner
{
public StreamScanner(Stream stream) { str = stream; }
private 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) throw new EndOfStreamException();
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);
return (char)b;
}
public string Line()
{
var sb = new StringBuilder();
for (var b = Char(); b != 10 && !isEof; b = (char)read()) sb.Append(b);
return sb.ToString();
}
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 long Integer()
{
long ret = 0; byte b = 0; var ng = false;
do b = read();
while (b != '-' && (b < '0' || '9' < b));
if (b == '-') { ng = true; b = read(); }
for (; true; b = read())
{
if (b < '0' || '9' < b) return ng ? -ret : ret;
else ret = ret * 10 + b - '0';
}
}
public ulong UInteger()
{
ulong ret = 0; byte b = 0;
do b = read();
while (b < '0' || '9' < b);
for (; true; b = read())
{
if (b < '0' || '9' < b) return ret;
else ret = ret * 10 + b - '0';
}
}
public double Double() { return double.Parse(Scan()); }
}
class Graph
{
public struct Edge
{
public int src, to;
public long cost;
public Edge(int _src, int _to, long _cost)
{
src = _src;
to = _to;
cost = _cost;
}
public Edge(int _to, long _cost)
{
src = -1;
to = _to;
cost = _cost;
}
}
int n;
public int Size => n;
public List<Edge>[] e;
public Graph(List<int>[] _g)
{
n = _g.Length;
e = new List<Edge>[n];
for (int i = 0; i < n; i++) e[i] = new List<Edge>();
for (int i = 0; i < n; i++)
foreach (var j in _g[i])
e[i].Add(new Edge(i, j, 1));
}
public Graph(int _n)
{
n = _n;
e = new List<Edge>[n];
for (int i = 0; i < n; i++) e[i] = new List<Edge>();
}
public void AddEdge(int x, int y, long cost = 1)
{
e[x].Add(new Edge(x, y, cost));
e[y].Add(new Edge(y, x, cost));
}
public void AddDirectedEdge(int src, int to, long cost = 1)
{
e[src].Add(new Edge(src, to, cost));
}
}
interface IReRootingDPOperator<T, S>
{
S SIdentity { get; }
S TtoS(T t);
S Merge(S x, S y);
T AddRoot(int i, int j, S x);
}
class ReRootingDP<T, S, Op> where Op : IReRootingDPOperator<T, S>
{
int n;
Op op = default;
List<int>[] edges;
T[] ans;
Dictionary<int, T>[] dp;
public T this[int i, int j] { get => dp[i][j]; }
public T this[int i] { get => ans[i]; }
public ReRootingDP(int _n)
{
n = _n;
edges = new List<int>[n];
for (int i = 0; i < n; i++) edges[i] = new List<int>();
}
public void AddEdge(int u, int v)
{
edges[u].Add(v);
edges[v].Add(u);
}
public void Calc()
{
dp = new Dictionary<int, T>[n];
for (int i = 0; i < n; i++) dp[i] = new Dictionary<int, T>();
seen = new bool[n];
for (int i = 0; i < n; i++) if (!seen[i]) DFS1(i);
seen = new bool[n];
for (int i = 0; i < n; i++) if (!seen[i]) DFS2(i);
ans = new T[n];
for (int i = 0; i < n; i++) ans[i] = dp[i][-1];
}
bool[] seen;
private void DFS1(int x, int p = -1)
{
seen[x] = true;
S val = op.SIdentity;
foreach (var y in edges[x])
{
if (y == p) continue;
DFS1(y, x);
val = op.Merge(val, op.TtoS(dp[y][x]));
}
dp[x].Add(p, op.AddRoot(x, p, val));
}
private void DFS2(int x, int p = -1)
{
seen[x] = true;
int deg = edges[x].Count;
var dp_r = new S[deg + 1];
dp_r[deg] = op.SIdentity;
for (int i = deg - 1; i >= 0; i--) dp_r[i] = op.Merge(dp_r[i + 1], op.TtoS(dp[edges[x][i]][x]));
if (p != -1) dp[x].Add(-1, op.AddRoot(x, -1, dp_r[0]));
S sum_l = op.SIdentity;
for (int i = 0; i < deg; i++)
{
int y = edges[x][i];
if (y != p)
{
dp[x].Add(y, op.AddRoot(x, y, op.Merge(sum_l, dp_r[i + 1])));
DFS2(y, x);
}
sum_l = op.Merge(sum_l, op.TtoS(dp[edges[x][i]][x]));
}
}
}
class TreeDoubling
{
int n, log, root;
int[] depth;
long[] dist;
int[,] par;
public TreeDoubling(in Graph g, int _root = 0)
{
n = g.Size;
root = _root;
while ((1 << log) < n) log++;
if (log <= 0) log = 1;
depth = new int[n];
dist = new long[n];
par = new int[n, log];
for (int i = 0; i < n; i++)
for (int j = 0; j < log; j++)
par[i, j] = -1;
var st = new Stack<int>();
st.Push(root);
while (st.Count > 0)
{
int x = st.Pop();
for (int j = 0; j < log - 1 && par[x, j] > -1; j++) par[x, j + 1] = par[par[x, j], j];
foreach (var y in g.e[x])
{
if (y.to == par[x, 0]) continue;
depth[y.to] = depth[x] + 1;
dist[y.to] = dist[x] + y.cost;
par[y.to, 0] = x;
st.Push(y.to);
}
}
}
[MethodImpl(256)]
public int LCA(int x, int y)
{
if (depth[x] > depth[y]) { x ^= y; y ^= x; x ^= y; }
int diff = depth[y] - depth[x];
for (int i = 0; diff > 0; i++)
{
if ((diff & 1) == 1) y = par[y, i];
diff >>= 1;
}
if (x == y) return x;
for (int i = log - 1; i >= 0; i--)
{
if (par[x, i] != par[y, i])
{
x = par[x, i];
y = par[y, i];
}
}
return par[x, 0];
}
[MethodImpl(256)]
public long Dist(int x) => dist[x];
[MethodImpl(256)]
public long Dist(int x, int y) => dist[x] + dist[y] - 2 * dist[LCA(x, y)];
[MethodImpl(256)]
public bool OnPath(int x, int y, int a) => Dist(x, a) + Dist(a, y) == Dist(x, y);
[MethodImpl(256)]
public int Ancestor(int x, int k = 1)
{
if (depth[x] < k) return -1;
for (int i = 0; i < log; i++) if (((k >> i) & 1) == 1) x = par[x, i];
return x;
}
}
class TreeJump
{
int n, u, v;
TreeDoubling du, dv;
public TreeJump(in Graph g)
{
n = g.Size;
u = 0;
v = 0;
var qu = new Queue<(int x, int p)>();
qu.Enqueue((0, -1));
while (qu.Count > 0)
{
var x = qu.Dequeue();
foreach (var e in g.e[x.x]) if (x.p != e.to) qu.Enqueue((e.to, x.x));
if (qu.Count == 0) u = x.x;
}
qu.Enqueue((u, -1));
while (qu.Count > 0)
{
var x = qu.Dequeue();
foreach (var e in g.e[x.x]) if (x.p != e.to) qu.Enqueue((e.to, x.x));
if (qu.Count == 0) v = x.x;
}
du = new TreeDoubling(g, u);
dv = new TreeDoubling(g, v);
}
[MethodImpl(256)]
public int Jump(int x, int k)
{
if (du.Dist(x) >= k) return du.Ancestor(x, k);
if (dv.Dist(x) >= k) return dv.Ancestor(x, k);
return -1;
}
[MethodImpl(256)]
public int Jump(int x, int y, int k)
{
var d = du.Dist(x, y);
if (d < k) return -1;
return du.Dist(x, du.LCA(x, y)) >= k ? du.Ancestor(x, k) : du.Ancestor(y, (int)d - k);
}
}