c# - すべての組み合わせを検索

Question

選択した果物="banana,banana,cherry,kiwi,strawberry"

lookup List<string>

"banana,strawberry" (true)
"strawberry" (true)
"banana,banana,banana" (false)

選択したアイテムの一部だけでルックアップに完全に一致する場合は、結果としてアイテムを選択する必要があります。

これを行うための最良の方法は何ですか？

Answer 1

問題は、各アイテムをバッグに変換してから、バッグの封じ込めをテストすることです。

private IDictionary<string, int> StringToBag(string str)
{
    return str.Split(',').GroupBy(s => s).ToDictionary(g => g.Key, g => g.Count());
}

private bool BagContains(IDictionary<string, int> haystack, IDictionary<string, int> needle)
{
    return needle.All(kv => haystack.ContainsKey(kv.Key) && kv.Value <= haystack[kv.Key]);
}

var bag = StringToBag("banana,banana,cherry,kiwi,strawberry");
bool contained = BagContains(bag, StringToBag("banana,strawberry"));

Answer 2

オブジェクトが次のように初期化された場合：

string selected = "banana,banana,cherry,kiwi,strawberry";

List<string> lookup = new List<string>()
{
    "banana,strawberry",
    "strawberry",
    "banana,banana,banana"
};

そして、あなたはこのようにグループ化するための方法を持っていました：

Dictionary<string, int> ToGroupDictionary(string value)
{
    return value.Split(',')
        .GroupBy(s => s.Trim())
        .ToDictionary(g => g.Key, g => g.Count());
}

lookup次のように各文字列をテストできます。

var selectedDictionary = ToGroupDictionary(selected);

// ["banana", 2]
// ["cherry", 1]
// ["kiwi", 1]
// ["strawberry", 1]

foreach(string test in lookup)
{
    var testDictionary = ToGroupDictionary(test);
    testDictionary.Keys.ToList().ForEach(k =>
        Console.WriteLine(selectedDictionary.ContainsKey(k) && 
            selectedDictionary[k] >= testDictionary[k]));

    // [0] :=
    // ["banana", 1]
    // ["strawberry", 1]
    // true, banana and strawberry exist

    // [1] :=
    // ["strawberry", 1]
    // true, strawberry exists

    // [2] :=
    // ["banana", 3]
    // false, too many bananas
}            

Answer 3

これをチェックしてください：

    private static void LoadFruits(string Fruit, Dictionary<string, int> FruitDictionary)
    {
        if (FruitDictionary.ContainsKey(Fruit))
            FruitDictionary[Fruit] = FruitDictionary[Fruit] + 1;
        else
            FruitDictionary.Add(Fruit, 1);
    }

    private static bool HasFruit(string Fruit, Dictionary<string, int> FruitDictionary)
    {
        if (FruitDictionary.ContainsKey(Fruit) && FruitDictionary[Fruit] > 0)
        {
            FruitDictionary[Fruit] = FruitDictionary[Fruit] - 1;
            return true;
        }

        return false;
    }

        ...
        List<string> AllThefruits = new List<string>(){"banana" ,"banana","cherry","kiwi","strawberry"};

        Dictionary<string, int> FruitsDictionary = new Dictionary<string, int>();

        List<string> Combination1 = new List<string>() { "banana", "strawberry" }; 
        AllThefruits.ForEach(x => LoadFruits(x, FruitsDictionary));
        bool TestCombination1 = Combination1.All(x => HasFruit(x, FruitsDictionary)); //true
        FruitsDictionary.Clear();

        List<string> Combination2 = new List<string>() { "strawberry" };
        AllThefruits.ForEach(x => LoadFruits(x, FruitsDictionary));
        bool TestCombination2 = Combination2.All(x => HasFruit(x, FruitsDictionary)); //true
        FruitsDictionary.Clear();

        List<string> Combination3 = new List<string>() { "banana", "banana", "banana" };
        AllThefruits.ForEach(x => LoadFruits(x, FruitsDictionary));
        bool TestCombination3 = Combination3.All(x => HasFruit(x, FruitsDictionary)); //false
        FruitsDictionary.Clear();

        List<string> Combination4 = new List<string>() { "banana", "banana" };
        AllThefruits.ForEach(x => LoadFruits(x, FruitsDictionary));
        bool TestCombination4 = Combination4.All(x => HasFruit(x, FruitsDictionary)); //true

ただし、これが最善の解決策かどうかはわかりません。

Answer 4

public static bool CheckCombination(List<string> values, List<string> combinations)
{
    var valuesLookup = values.ToLookup(x => x);

    return CheckCombination(valuesLookup, combinations);
}

public static bool CheckCombination(ILookup<string, string> valuesLookup, List<string> combinations)
{
    foreach (var combination in combinations.GroupBy(x => x))
    {
        if (valuesLookup.Contains(combination.Key) &&
            valuesLookup[combination.Key].Count() < combination.Count())
            return false;
    }
    return true;
}

Answer 5

テストされていませんが、これは機能します：

string fr = "banana,banana,cherry,kiwi,strawberry";
    IList<string> selFr = fr.Split(new string[] { "," }, StringSplitOptions.None);
    IList<string> look = new List<string>();
    // Add the lookup values to the "look" list here...
    IList<string> res = new List<string>();
    foreach (string lookupStr in look) {
        foreach (string f in selFr) {
            if (lookupStr.Contains(f)) {
                  res.Add(lookupStr);
                  continue;
            }
        }
     }
  return res;