ABC138-D Ki

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 3");
            WillReturn.Add("1 2");
            WillReturn.Add("2 3");
            WillReturn.Add("2 4");
            WillReturn.Add("2 10");
            WillReturn.Add("1 100");
            WillReturn.Add("3 1");
            //100 110 111 110
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("6 2");
            WillReturn.Add("1 2");
            WillReturn.Add("1 3");
            WillReturn.Add("2 4");
            WillReturn.Add("3 6");
            WillReturn.Add("2 5");
            WillReturn.Add("1 10");
            WillReturn.Add("1 10");
            //20 20 20 20 20 20
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    struct JyoutaiDef
    {
        internal int CurrNode;
        internal int SumVal;
    }

    // 隣接リスト
    static Dictionary<int, List<int>> mToNodeListDict = new Dictionary<int, List<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]);
        int N = wkArr[0];
        int Q = wkArr[1];

        foreach (string EachStr in InputList.Skip(1).Take(N - 1)) {
            SplitAct(EachStr);
            int FromNode = wkArr[0];
            int ToNode = wkArr[1];

            if (mToNodeListDict.ContainsKey(FromNode) == false) {
                mToNodeListDict[FromNode] = new List<int>();
            }
            if (mToNodeListDict.ContainsKey(ToNode) == false) {
                mToNodeListDict[ToNode] = new List<int>();
            }
            mToNodeListDict[FromNode].Add(ToNode);
            mToNodeListDict[ToNode].Add(FromNode);
        }

        int[] ValArr = new int[N + 1];
        foreach (string EachStr in InputList.Skip(N)) {
            SplitAct(EachStr);
            ValArr[wkArr[0]] += wkArr[1];
        }

        var Stk = new Stack<JyoutaiDef>();
        JyoutaiDef WillPush;
        WillPush.CurrNode = 1;
        WillPush.SumVal = ValArr[1];
        Stk.Push(WillPush);

        var VisitedSet = new HashSet<int>();
        VisitedSet.Add(1);
        var PoppedList = new List<JyoutaiDef>();
        while (Stk.Count > 0) {
            JyoutaiDef Popped = Stk.Pop();
            PoppedList.Add(Popped);

            // 子ノード無しの場合
            if (mToNodeListDict.ContainsKey(Popped.CurrNode) == false)
                continue;

            foreach (int EachToNode in mToNodeListDict[Popped.CurrNode]) {
                if (VisitedSet.Add(EachToNode)) {

                    WillPush.CurrNode = EachToNode;
                    WillPush.SumVal = Popped.SumVal + ValArr[EachToNode];
                    Stk.Push(WillPush);
                }
            }
        }

        var Query = PoppedList.OrderBy(pX => pX.CurrNode);
        var WillOutIntList = new List<int>();
        foreach (var EachItem in Query) {
            WillOutIntList.Add(EachItem.SumVal);
        }
        string[] WillOutStrArr = Array.ConvertAll(WillOutIntList.ToArray(), pX => pX.ToString());
        Console.WriteLine(string.Join(" ", WillOutStrArr));
    }
}

解説

各ノードにカウンターの値を足しておいてから、
根からの深さ優先探索を行い、累積和を求めるようにしてます。