ALDS1_5_A: Exhaustive Search

問題へのリンク

C#のソース

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

// Q015 全探索 https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_5_A&lang=jp
class Program
{
    static string InputPattern = "InputX";

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

        if (InputPattern == "Input1") {
            WillReturn.Add("5");
            WillReturn.Add("1 5 7 10 21");
            WillReturn.Add("4");
            WillReturn.Add("2 4 17 8");
            //no
            //no
            //yes
            //yes
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static void Main()
    {
        List<string> InputList = GetInputList();
        int[] AArr = InputList[1].Split(' ').Select(X => int.Parse(X)).ToArray();
        int[] MArr = InputList[3].Split(' ').Select(X => int.Parse(X)).ToArray();

        //作れる数のHashSet
        var MakeNumSet = new HashSet<int>();
        MakeNumSet.Add(0);

        for (int I = 0; I <= AArr.GetUpperBound(0); I++) {
            foreach (int EachInt in MakeNumSet.ToArray()) {
                MakeNumSet.Add(EachInt + AArr[I]);
            }
        }

        foreach (int EachInt in MArr) {
            if (MakeNumSet.Contains(EachInt)) {
                Console.WriteLine("yes");
            }
            else {
                Console.WriteLine("no");
            }
        }
    }
}

解説

動的計画法で
作れる数のHashSetを更新してます。