键值对列表 [英] Key Value Pair List

问题描述

我有以下元素的列表：

{[A,1] ; [B,0] ; [C,0] ; [D,2]; [E,0] ; [F,8]}

当变量= 3 - >我想返回值是A，D

When Variable =3 -> i want the return value to be A,D

当变量= 11 - >返回值是A，D，F

When variable =11 -> return value to be A, D, F

在2 - >返回值为D

when 2 -> return value to be D

等。

 int sum = myList.Sum(x => x.Value) 

如何得到相应的键（A，D，F）？

how to get the corresponding Key (A,D,F)?

推荐答案

使用的子集中的一的方法<一href=\"http://stackoverflow.com/questions/13765699/how-can-i-obtain-all-the-possible-combination-of-a-subset\">this问题

var list = new List<KeyValuePair<string, int>>() { 
    new KeyValuePair<string, int>("A", 1),
    new KeyValuePair<string, int>("B", 0),
    new KeyValuePair<string, int>("C", 0),
    new KeyValuePair<string, int>("D", 2),
    new KeyValuePair<string, int>("E", 8),
};

int input = 11;
var items = SubSets(list).FirstOrDefault(x => x.Sum(y => y.Value)==input);

---

修改

一个完整的控制台应用程序：

a full console application:

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

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            var list = new List<KeyValuePair<string, int>>() { 
                new KeyValuePair<string, int>("A", 1),
                new KeyValuePair<string, int>("B", 2),
                new KeyValuePair<string, int>("C", 3),
                new KeyValuePair<string, int>("D", 4),
                new KeyValuePair<string, int>("E", 5),
                new KeyValuePair<string, int>("F", 6),
            };

            int input = 12;
            var alternatives = list.SubSets().Where(x => x.Sum(y => y.Value) == input);

            foreach (var res in alternatives)
            {
                Console.WriteLine(String.Join(",", res.Select(x => x.Key)));
            }
            Console.WriteLine("END");
            Console.ReadLine();
        }
    }

    public static class Extenions
    {
        public static IEnumerable<IEnumerable<T>> SubSets<T>(this IEnumerable<T> enumerable)
        {
            List<T> list = enumerable.ToList();
            ulong upper = (ulong)1 << list.Count;

            for (ulong i = 0; i < upper; i++)
            {
                List<T> l = new List<T>(list.Count);
                for (int j = 0; j < sizeof(ulong) * 8; j++)
                {
                    if (((ulong)1 << j) >= upper) break;

                    if (((i >> j) & 1) == 1)
                    {
                        l.Add(list[j]);
                    }
                }

                yield return l;
            }
        }
    }
}

这篇关于键值对列表的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！