結果
問題 | No.806 木を道に |
ユーザー | mnzn |
提出日時 | 2020-04-11 05:12:05 |
言語 | C#(csc) (csc 3.9.0) |
結果 |
WA
|
実行時間 | - |
コード長 | 9,841 bytes |
コンパイル時間 | 984 ms |
コンパイル使用メモリ | 110,848 KB |
実行使用メモリ | 52,016 KB |
最終ジャッジ日時 | 2024-09-17 08:22:23 |
合計ジャッジ時間 | 7,084 ms |
ジャッジサーバーID (参考情報) |
judge2 / judge1 |
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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 | 31 ms
18,944 KB |
testcase_01 | AC | 31 ms
18,944 KB |
testcase_02 | WA | - |
testcase_03 | WA | - |
testcase_04 | AC | 31 ms
18,816 KB |
testcase_05 | WA | - |
testcase_06 | WA | - |
testcase_07 | AC | 32 ms
18,944 KB |
testcase_08 | AC | 31 ms
18,944 KB |
testcase_09 | AC | 31 ms
18,816 KB |
testcase_10 | WA | - |
testcase_11 | WA | - |
testcase_12 | WA | - |
testcase_13 | WA | - |
testcase_14 | WA | - |
testcase_15 | WA | - |
testcase_16 | WA | - |
testcase_17 | WA | - |
testcase_18 | WA | - |
testcase_19 | WA | - |
testcase_20 | WA | - |
testcase_21 | WA | - |
testcase_22 | WA | - |
testcase_23 | WA | - |
testcase_24 | AC | 115 ms
33,144 KB |
testcase_25 | AC | 176 ms
39,920 KB |
testcase_26 | AC | 87 ms
32,116 KB |
testcase_27 | AC | 219 ms
52,016 KB |
testcase_28 | AC | 37 ms
19,820 KB |
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.Collections; using System.Collections.Generic; using System.IO; using System.Linq; class Program { static void Main(string[] args) { var N = sc.ReadInt(); var G = new List<int>[N]; var dij = new Dijkstra(N); for (int i = 0; i < N; i++) { G[i] = new List<int>(); } for (int i = 0; i < N - 1; i++) { var x = sc.ReadInt() - 1; var y = sc.ReadInt() - 1; dij.Add(x, y, -1); dij.Add(y, x, -1); } var dist = dij.Calc(0); var p1 = Array.IndexOf(dist, dist.Min()); dist = dij.Calc(p1); var diameter = -dist.Min(); var ans = N - diameter - 1; Console.WriteLine(ans); } class Dijkstra { public int V { get; set; } public int E { get; set; } public List<Edge>[] G { get; set; } public Dijkstra(int n) { this.V = n; this.G = new List<Edge>[V]; for (int i = 0; i < V; i++) { this.G[i] = new List<Edge>(); } } public void Add(int a, int b, long cost = 1) { this.G[a].Add(new Edge(b, cost)); this.G[b].Add(new Edge(a, cost)); this.E++; } public long GetMinCost(int start, int goal) { var cost = new long[V]; for (int i = 0; i < V; i++) cost[i] = long.MaxValue; cost[start] = 0; var capacity = Math.Max(1, E); var q = new PriorityQueue<P>(capacity, false); q.Enqueue(new P(start, 0)); while (q.Count > 0) { var p = q.Dequeue(); if (p.Cost != cost[p.A]) continue; foreach (var e in this.G[p.A]) { if (cost[e.To] > p.Cost + e.Cost) { cost[e.To] = p.Cost + e.Cost; q.Enqueue(new P(e.To, cost[e.To])); } } } return cost[goal] == long.MaxValue ? -1 : cost[goal]; } public long[] Calc(int start) { var visited = new bool[V]; var cost = new long[V]; for (int i = 0; i < V; i++) cost[i] = long.MaxValue; cost[start] = 0; var capacity = Math.Max(1, E); var q = new PriorityQueue<P>(capacity, false); q.Enqueue(new P(start, 0)); while (q.Count > 0) { var p = q.Dequeue(); visited[p.A] = true; if (p.Cost != cost[p.A]) continue; foreach (var e in this.G[p.A]) { if (cost[e.To] > p.Cost + e.Cost && !visited[e.To]) { cost[e.To] = p.Cost + e.Cost; q.Enqueue(new P(e.To, cost[e.To])); } } } return cost; } public struct Edge { public int To; public long Cost; public Edge(int to, long cost) { this.To = to; this.Cost = cost; } } public struct P : IComparable<P> { public int A; public long Cost; public P(int a, long cost) { this.A = a; this.Cost = cost; } public int CompareTo(P other) { return this.Cost.CompareTo(other.Cost); } } } class PriorityQueue<T> { public readonly T[] Array; public readonly bool Greater; public int Count { get; private set; } = 0; private IComparer<T> Cmp; public PriorityQueue(int capacity, bool greater = true, IComparer<T> cmp = null) { this.Cmp = cmp; if (cmp == null) { this.Cmp = Comparer<T>.Default; } this.Array = new T[capacity]; this.Greater = greater; } public void Enqueue(T item) { this.Array[this.Count] = item; this.Count += 1; this.UpHeap(); } public T Dequeue() { this.Swap(0, this.Count - 1); this.Count -= 1; this.DownHeap(); return this.Array[this.Count]; } public T Peek() { return this.Array[0]; } private void UpHeap() { var n = this.Count - 1; while (n != 0) { var parent = (n - 1) / 2; if (this.Compare(this.Array[n], this.Array[parent]) > 0) { this.Swap(n, parent); n = parent; } else { break; } } } private void DownHeap() { var parent = 0; while (true) { var child = 2 * parent + 1; if (child > this.Count - 1) break; if (child < this.Count - 1 && this.Compare(this.Array[child], this.Array[child + 1]) < 0) { child += 1; } if (this.Compare(this.Array[parent], this.Array[child]) < 0) { this.Swap(parent, child); parent = child; } else { break; } } } private int Compare(T a, T b) { var c = this.Cmp.Compare(a, b); if (!this.Greater) { c = -c; } return c; } private void Swap(int a, int b) { var tmp = this.Array[a]; this.Array[a] = this.Array[b]; this.Array[b] = tmp; } } static Scanner sc = new Scanner(); } class Scanner { string[] S = new string[0]; int Index = 0; char[] Separators = new char[] { ' ' }; public string Next() { if (this.Index < this.S.Length) return this.S[this.Index++]; var line = ""; while (line == "") line = Console.ReadLine(); this.S = line.Split(this.Separators, StringSplitOptions.RemoveEmptyEntries); if (this.S.Length == 0) return this.Next(); this.Index = 0; return this.S[this.Index++]; } public string ReadStr() { return this.Next(); } public char ReadChar() { return this.Next()[0]; } public int ReadInt() { return int.Parse(this.Next()); } public uint ReadUInt() { return uint.Parse(this.Next()); } public long ReadLong() { return long.Parse(this.Next()); } public double ReadDouble() { return double.Parse(this.Next()); } public Tuple<int, int> ReadTup(int add = 0) { return Tuple.Create(this.ReadInt() + add, this.ReadInt() + add); } public Tuple<long, long> ReadTupLong(int add = 0) { return Tuple.Create(this.ReadLong() + add, this.ReadLong() + add); } public Tuple<int, int, int> ReadTup3(int add = 0) { return Tuple.Create(this.ReadInt() + add, this.ReadInt() + add, this.ReadInt() + add); } public Tuple<int, int, int, int> ReadTup4(int add = 0) { return Tuple.Create(this.ReadInt() + add, this.ReadInt() + add, this.ReadInt() + add, this.ReadInt() + add); } public int[] ReadIntArray(int n) { var array = new int[n]; for (int i = 0; i < array.Length; i++) { array[i] = this.ReadInt(); } return array; } public long[] ReadLongArray(int n) { var array = new long[n]; for (int i = 0; i < array.Length; i++) { array[i] = this.ReadLong(); } return array; } public double[] ReadDoubleArray(int n) { var array = new double[n]; for (int i = 0; i < array.Length; i++) { array[i] = this.ReadDouble(); } return array; } public char[] ReadCharArray(int n) { var array = new char[n]; for (int i = 0; i < array.Length; i++) { array[i] = this.ReadChar(); } return array; } public string[] ReadStrArray(int n) { var array = new string[n]; for (int i = 0; i < array.Length; i++) { array[i] = this.ReadStr(); } return array; } public Tuple<long, long>[] ReadTupLongArray(int n, int add = 0) { var array = new Tuple<long, long>[n]; for (int i = 0; i < n; i++) { array[i] = this.ReadTupLong(add); } return array; } public Tuple<int, int>[] ReadTupArray(int n, int add = 0) { var array = new Tuple<int, int>[n]; for (int i = 0; i < n; i++) { array[i] = this.ReadTup(add); } return array; } public Tuple<int, int, int>[] ReadTup3Array(int n, int add = 0) { var array = new Tuple<int, int, int>[n]; for (int i = 0; i < n; i++) { array[i] = this.ReadTup3(add); } return array; } public Tuple<int, int, int, int>[] ReadTup4Array(int n, int add = 0) { var array = new Tuple<int, int, int, int>[n]; for (int i = 0; i < n; i++) { array[i] = this.ReadTup4(add); } return array; } }