ABC348-D Medicines on Grid

問題へのリンク

C#のソース

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static string InputPattern = "InputX";

    static List<string> GetInputList()
    {
        var WillReturn = new List<string>();

        if (InputPattern == "Input1") {
            WillReturn.Add("4 4");
            WillReturn.Add("S...");
            WillReturn.Add("#..#");
            WillReturn.Add("#...");
            WillReturn.Add("..#T");
            WillReturn.Add("4");
            WillReturn.Add("1 1 3");
            WillReturn.Add("1 3 5");
            WillReturn.Add("3 2 1");
            WillReturn.Add("2 3 1");
            //Yes
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("2 2");
            WillReturn.Add("S.");
            WillReturn.Add("T.");
            WillReturn.Add("1");
            WillReturn.Add("1 2 4");
            //No
        }
        else if (InputPattern == "Input3") {
            WillReturn.Add("4 5");
            WillReturn.Add("..#..");
            WillReturn.Add(".S##.");
            WillReturn.Add(".##T.");
            WillReturn.Add(".....");
            WillReturn.Add("3");
            WillReturn.Add("3 1 5");
            WillReturn.Add("1 2 3");
            WillReturn.Add("2 2 1");
            //Yes
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static int mH;
    static int mW;

    static int UB_X;
    static int UB_Y;

    static char[,] mBanArr;

    static int mStaX;
    static int mStaY;
    static int mGoalX;
    static int mGoalY;

    // 薬の値[座標のハッシュ値]
    static Dictionary<int, int> mKusuriDict = new Dictionary<int, int>();

    static void Main()
    {
        List<string> InputList = GetInputList();

        int[] wkArr = { };
        Action<string> SplitAct = pStr =>
            wkArr = pStr.Split(' ').Select(pX => int.Parse(pX)).ToArray();

        SplitAct(InputList[0]);
        mH = wkArr[0];
        mW = wkArr[1];
        UB_Y = mH - 1;
        UB_X = mW - 1;

        mBanArr = CreateBanArr(InputList.Skip(1).Take(mH));

        foreach (string Eachstr in InputList.Skip(1 + mH + 1)) {
            SplitAct(Eachstr);
            int CurrY = wkArr[0] - 1;
            int CurrX = wkArr[1] - 1;
            int CurrHash = GetHash(CurrX, CurrY);
            int Val = wkArr[2];
            mKusuriDict[CurrHash] = Val;
        }

        for (int X = 0; X <= UB_X; X++) {
            for (int Y = 0; Y <= UB_Y; Y++) {
                if (mBanArr[X, Y] == 'S') {
                    mStaX = X; mStaY = Y;
                }
                if (mBanArr[X, Y] == 'T') {
                    mGoalX = X; mGoalY = Y;
                }
            }
        }

        var Que = new Queue<JyouatiDef>();
        JyouatiDef WillEnqueue;
        WillEnqueue.CurrX = mStaX;
        WillEnqueue.CurrY = mStaY;
        WillEnqueue.HP = 0;
        Que.Enqueue(WillEnqueue);

        // 最大HP[座標のハッシュ値]
        var EdakiriDict = new Dictionary<int, int>();

        while (Que.Count > 0) {
            JyouatiDef Dequeued = Que.Dequeue();

            int CurrHash = GetHash(Dequeued.CurrX, Dequeued.CurrY);

            // クリア判定
            if (Dequeued.CurrX == mGoalX && Dequeued.CurrY == mGoalY) {
                Console.WriteLine("Yes");
                return;
            }

            if (mKusuriDict.ContainsKey(CurrHash)) {
                Dequeued.HP = Math.Max(Dequeued.HP, mKusuriDict[CurrHash]);
            }

            if (Dequeued.HP == 0) continue;

            Action<int, int> EnqueueAct = (pNewX, pNewY) =>
            {
                if (pNewX < 0 || UB_X < pNewX) return;
                if (pNewY < 0 || UB_Y < pNewY) return;

                if (mBanArr[pNewX, pNewY] == '#') return;

                WillEnqueue.CurrX = pNewX;
                WillEnqueue.CurrY = pNewY;
                WillEnqueue.HP = Dequeued.HP - 1;

                int NewHash = GetHash(pNewX, pNewY);
                if (EdakiriDict.ContainsKey(NewHash)) {
                    if (EdakiriDict[NewHash] >= WillEnqueue.HP) {
                        return;
                    }
                }
                EdakiriDict[NewHash] = WillEnqueue.HP;

                Que.Enqueue(WillEnqueue);
            };

            EnqueueAct(Dequeued.CurrX, Dequeued.CurrY - 1);
            EnqueueAct(Dequeued.CurrX, Dequeued.CurrY + 1);
            EnqueueAct(Dequeued.CurrX - 1, Dequeued.CurrY);
            EnqueueAct(Dequeued.CurrX + 1, Dequeued.CurrY);
        }
        Console.WriteLine("No");
    }

    struct JyouatiDef
    {
        internal int CurrX;
        internal int CurrY;
        internal int HP;
    }

    // 座標のハッシュ値を返す
    static int GetHash(int pX, int pY)
    {
        int Hash = pX * 1000;
        Hash += pY;
        return Hash;
    }

    ////////////////////////////////////////////////////////////////
    // IEnumerable<string>をcharの2次元配列に設定する
    ////////////////////////////////////////////////////////////////
    static char[,] CreateBanArr(IEnumerable<string> pStrEnum)
    {
        var StrList = pStrEnum.ToList();
        if (StrList.Count == 0) {
            return new char[0, 0];
        }
        int UB_X = StrList[0].Length - 1;
        int UB_Y = StrList.Count - 1;

        char[,] WillReturn = new char[UB_X + 1, UB_Y + 1];

        for (int Y = 0; Y <= UB_Y; Y++) {
            for (int X = 0; X <= UB_X; X++) {
                WillReturn[X, Y] = StrList[Y][X];
            }
        }
        return WillReturn;
    }
}

解説

最大HP[座標のハッシュ値]で枝切りするBFSで解いてます。