結果
問題 | No.20 砂漠のオアシス |
ユーザー | sekiya9311 |
提出日時 | 2017-10-14 22:42:18 |
言語 | C#(csc) (csc 3.9.0) |
結果 |
AC
|
実行時間 | 96 ms / 5,000 ms |
コード長 | 11,821 bytes |
コンパイル時間 | 1,150 ms |
コンパイル使用メモリ | 116,664 KB |
実行使用メモリ | 24,960 KB |
最終ジャッジ日時 | 2024-11-17 14:52:52 |
合計ジャッジ時間 | 2,998 ms |
ジャッジサーバーID (参考情報) |
judge1 / judge2 |
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ファイルパターン | 結果 |
---|---|
other | AC * 21 |
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.Generic;using System.Linq;using System.Text;namespace ProgrammingContest{class MainClass : IDisposable{Scanner sc;Writer wr;string backPath = "..";char dirSep = System.IO.Path.DirectorySeparatorChar;string inFilePath = null;string outFilePath = null;public MainClass(){this.inFilePath = this.backPath+ this.dirSep+ this.backPath+ this.dirSep+ "in.txt";this.outFilePath = this.backPath+ this.dirSep+ this.backPath+ this.dirSep+ "out.txt";}static void Main(string[] args){using (var mainClass = new MainClass()){//mainClass.MakeTestCase();mainClass.Solve();}}public void Dispose(){if (this.sc != null){this.sc.Dispose();this.sc = null;}if (this.wr != null){this.wr.Dispose();this.wr = null;}}void MakeTestCase(){Random rand = new Random();var res = new StringBuilder();using (var writer = new System.IO.StreamWriter(inFilePath))writer.Write(res.ToString());}void Solve(){this.wr = new Writer(this.isReactive);//this.wr = new Writer(this.outFilePath);#if DEBUGif (!this.isReactive)this.sc = new Scanner(this.inFilePath);elsethis.sc = new Scanner();#elsethis.sc = new Scanner();#endifN = sc.NextInt;V = sc.NextInt;oasis = new Point { x = sc.NextInt - 1, y = sc.NextInt - 1 };L = new int[N, N];for (int i = 0; i < N; i++){for (int j = 0; j < N; j++){L[i, j] = sc.NextInt;}}var st = new Point() { x = 0, y = 0 };var ed = new Point() { x = N - 1, y = N - 1 };string ans = "NO";if (Dijkstra(st, ed) < V){ans = "YES";}else if (!oasis.Equals(new Point() { x = -1, y = -1 })){int f = Dijkstra(st, oasis);if (f < V){int ff = Dijkstra(oasis, ed);//wr.WriteLine("{0} {1} {2}", f, ff, V);if (ff < (V - f) * 2){ans = "YES";}}}wr.WriteLine(ans);}int Dijkstra(Point st, Point ed){var heap = new SkewHeap<State>();heap.Push(new State(st));int[,] u = new int[N, N];for (int i = 0; i < N; i++){for (int j = 0; j < N; j++){u[i, j] = (int)1e9;}}u[st.y, st.x] = 0;int preCost = 0;while (!heap.IsEmpty()){var state = heap.Poll();if (preCost > state.Cost) throw new Exception();preCost = state.Cost;if (state.p.Equals(ed)){return state.Cost;}var nextPoint = state.p.Next();foreach (var p in nextPoint){if (Inside(p)){int nextCost = state.Cost + L[p.y, p.x];if (nextCost < u[p.y, p.x]){u[p.y, p.x] = nextCost;heap.Push(new State(p, nextCost));}}}}return -1;}int N, V;Point oasis;int[,] L;bool Inside(Point p){return 0 <= p.x && p.x < N && 0 <= p.y && p.y < N;}struct State : IComparable<State>{public Point p;public int Cost;public State(int nx, int ny){p = new Point { x = nx, y = ny };Cost = 0;}public State(Point p, int cost = 0){this.p = p;this.Cost = cost;}public int CompareTo(State other){return Math.Sign(this.Cost - other.Cost);}}struct Point{public int x, y;static Point[] dPoint = new Point[]{new Point{ x = 0, y = -1},new Point{ x = -1, y = 0},new Point{ x = 0, y = 1},new Point{ x = 1, y = 0},};private Point Next(Point d){return new Point { x = this.x + d.x, y = this.y + d.y };}public List<Point> Next(){List<Point> ret = new List<Point>();foreach (var el in dPoint){ret.Add(this.Next(el));}if (ret.Count != 4) throw new Exception();return ret;}public override bool Equals(object other){return (other is Point)&& ((Point)other).x == this.x&& ((Point)other).y == this.y;}}bool isReactive = false; // TODO: reactive check !!}class SkewHeap<T> where T : IComparable<T>{private class HeapNode{public HeapNode l, r;public T val;public static Func<T, T, int> CompareTo;public HeapNode(T val){this.val = val;l = r = null;}public static HeapNode Meld(HeapNode leftNode, HeapNode rightNode){if (leftNode == null){return rightNode;}if (rightNode == null){return leftNode;}if (HeapNode.CompareTo(leftNode.val, rightNode.val) > 0){var t = rightNode;rightNode = leftNode;leftNode = t;}leftNode.r = Meld(leftNode.r, rightNode);var t2 = leftNode.l;leftNode.l = leftNode.r;leftNode.r = t2;return leftNode;}}private HeapNode topNode;private int count_;public int Count { get { return this.count_; } }public SkewHeap(Func<T, T, int> comp = null){HeapNode.CompareTo = (comp ?? ((T l, T r) => l.CompareTo(r)));this.topNode = null;this.count_ = 0;}public void Pop(){this.topNode = HeapNode.Meld(this.topNode.l, this.topNode.r);this.count_--;}public T Top(){return this.topNode.val;}public void Push(T val){this.topNode = HeapNode.Meld(this.topNode, new HeapNode(val));this.count_++;}public T Poll(){T retVal = this.Top();this.Pop();return retVal;}public bool IsEmpty(){return this.topNode == null;}public void Merge(SkewHeap<T> otherHeap){this.count_ += otherHeap.Count;this.topNode = HeapNode.Meld(this.topNode, otherHeap.topNode);}}class Writer : IDisposable{System.IO.TextWriter writer;StringBuilder sb;bool isReactive;public Writer(string path) : this(new System.IO.StreamWriter(path)){}public Writer(bool isReactive) : this(null, isReactive){}public Writer(System.IO.TextWriter writer = null, bool isReactive = false){this.writer = (writer ?? Console.Out);if (!(this.isReactive = isReactive)){this.sb = new StringBuilder();}}public void Dispose(){if (!isReactive)this.writer.Write(sb.ToString());if (!this.writer.Equals(Console.Out))this.writer.Dispose();}public void Write(object val){if (this.isReactive){this.writer.Write(val.ToString());this.writer.Flush();}elsethis.sb.Append(val.ToString());}public void Write(string format, params object[] vals){if (this.isReactive){this.writer.Write(format, vals);this.writer.Flush();}elsethis.sb.AppendFormat(format, vals);}public void WriteLine(object val){this.Write(val.ToString() + System.Environment.NewLine);}public void WriteLine(string format, params object[] vals){this.Write(format + System.Environment.NewLine, vals);}}class Scanner : IDisposable{Queue<string> buffer;char[] sep;System.IO.TextReader reader;public Scanner(string path) : this(new System.IO.StreamReader(path)){}public Scanner(System.IO.TextReader reader = null){this.buffer = new Queue<string>();this.sep = new char[] { ' ' };this.reader = (reader ?? Console.In);}private void CheckBuffer(){if (this.buffer.Count == 0){string str = null;while (string.IsNullOrEmpty(str)){str = this.reader.ReadLine();}string[] sreArray = str.Split(this.sep);foreach (string elStr in sreArray){this.buffer.Enqueue(elStr);}}}public void Dispose(){if (!this.reader.Equals(Console.In))this.reader.Dispose();}public string Next{get{this.CheckBuffer();return this.buffer.Dequeue();}}public int NextInt{get{return int.Parse(this.Next);}}public double NextDouble{get{return double.Parse(this.Next);}}public long NextLong{get{return long.Parse(this.Next);}}public bool IsEmpty{get{this.CheckBuffer();return this.buffer.Count == 0;}}}}