C#:没有重复的骰子排列

Question

如何更改下面的C#代码以列出所有可能的排列而不重复？例如:2个骰子卷的结果将产生1,1,2,因此不应出现2,1,1.

以下是我的代码:

string[] Permutate(int input)
{
        string[] dice;
        int numberOfDice = input;
        const int diceFace = 6;
        dice = new string[(int)Math.Pow(diceFace, numberOfDice)];
        int indexNumber = (int)Math.Pow(diceFace, numberOfDice);
        int range = (int)Math.Pow(diceFace, numberOfDice) / 6;

        int diceNumber = 1;
        int counter = 0;

        for (int i = 1; i <= indexNumber; i++)
        {
            if (range != 0)
            {
                dice[i - 1] += diceNumber + " ";
                counter++;
                if (counter == range)
                {
                    counter = 0;
                    diceNumber++;
                }
                if (i == indexNumber)
                {
                    range /= 6;
                    i = 0;
                }
                if (diceNumber == 7)
                {
                    diceNumber = 1;
                }
            }
            Thread.Sleep(1);
        }
        return dice;
    }

Answer 1

我能想到的最简单的方式:

List<string> dices = new List<string>();
for (int i = 1; i <= 6; i++)
{
    for (int j = i; j <= 6; j++)
    {
        for (int k = j; k <= 6; k++)
        {
            dices.Add(string.Format("{0} {1} {2}", i, j, k));
        }
    }
}

Answer 2

我数学也不好，这可能有帮助，也可能没有帮助......

程序.cs

namespace Permutation
{
    using System;
    using System.Collections.Generic;

    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Generating list.");

            var dice = new List<ThreeDice>();

            for (int x = 1; x <= 6; x++)
            {
                for (int y = 1; y <= 6; y++)
                {
                    for (int z = 1; z <= 6; z++)
                    {
                        var die = new ThreeDice(x, y, z);

                        if (dice.Contains(die))
                        {
                            Console.WriteLine(die + " already exists.");
                        }
                        else
                        {
                            dice.Add(die);
                        }
                    }
                }
            }

            Console.WriteLine(dice.Count + " permutations generated.");

            foreach (var die in dice)
            {
                Console.WriteLine(die);
            }

            Console.ReadKey();
        }
    }
}

ThreeDice.cs

namespace Permutation
{
    using System;
    using System.Collections.Generic;

    public class ThreeDice : IEquatable<ThreeDice>
    {
        public ThreeDice(int dice1, int dice2, int dice3)
        {
            this.Dice = new int[3];
            this.Dice[0] = dice1;
            this.Dice[1] = dice2;
            this.Dice[2] = dice3;
        }

        public int[] Dice { get; private set; }

        // IEquatable implements this method. List.Contains() will use this method to see if there's a match.
        public bool Equals(ThreeDice other)
        {
            // Get the current dice values into a list.
            var currentDice = new List<int>(this.Dice);

            // Check to see if the same values exist by removing them one by one.
            foreach (int die in other.Dice)
            {
                currentDice.Remove(die);
            }

            // If the list is empty, we have a match.
            return currentDice.Count == 0;
        }

        public override string ToString()
        {
            return "<" + this.Dice[0] + "," + this.Dice[1] + "," + this.Dice[2] + ">";
        }
    }
}

祝你好运。