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orzFly/PermutationAndCombination.cs

Created June 28, 2015 13:06
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  1. orzFly created this gist Jun 28, 2015.
    155 changes: 155 additions & 0 deletions PermutationAndCombination.cs
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    using System;
    using System.Collections.Generic;
    using System.Text;

    namespace _4DigitalSolver
    {
    public class PermutationAndCombination<T>
    {
    /// <summary>
    /// 交换两个变量
    /// </summary>
    /// <param name="a">变量1</param>
    /// <param name="b">变量2</param>
    public static void Swap(ref T a, ref T b)
    {
    T temp = a;
    a = b;
    b = temp;
    }

    /// <summary>
    /// 递归算法求数组的组合(私有成员)
    /// </summary>
    /// <param name="list">返回的范型</param>
    /// <param name="t">所求数组</param>
    /// <param name="n">辅助变量</param>
    /// <param name="m">辅助变量</param>
    /// <param name="b">辅助数组</param>
    /// <param name="M">辅助变量M</param>
    private static void GetCombination(ref List<T[]> list, T[] t, int n, int m, int[] b, int M)
    {
    for (int i = n; i >= m; i--)
    {
    b[m - 1] = i - 1;
    if (m > 1)
    {
    GetCombination(ref list, t, i - 1, m - 1, b, M);
    }
    else
    {
    if (list == null)
    {
    list = new List<T[]>();
    }
    T[] temp = new T[M];
    for (int j = 0; j < b.Length; j++)
    {
    temp[j] = t[b[j]];
    }
    list.Add(temp);
    }
    }
    }

    /// <summary>
    /// 递归算法求排列(私有成员)
    /// </summary>
    /// <param name="list">返回的列表</param>
    /// <param name="t">所求数组</param>
    /// <param name="startIndex">起始标号</param>
    /// <param name="endIndex">结束标号</param>
    private static void GetPermutation(ref List<T[]> list, T[] t, int startIndex, int endIndex)
    {
    if (startIndex == endIndex)
    {
    if (list == null)
    {
    list = new List<T[]>();
    }
    T[] temp = new T[t.Length];
    t.CopyTo(temp, 0);
    list.Add(temp);
    }
    else
    {
    for (int i = startIndex; i <= endIndex; i++)
    {
    Swap(ref t[startIndex], ref t[i]);
    GetPermutation(ref list, t, startIndex + 1, endIndex);
    Swap(ref t[startIndex], ref t[i]);
    }
    }
    }

    /// <summary>
    /// 求从起始标号到结束标号的排列，其余元素不变
    /// </summary>
    /// <param name="t">所求数组</param>
    /// <param name="startIndex">起始标号</param>
    /// <param name="endIndex">结束标号</param>
    /// <returns>从起始标号到结束标号排列的范型</returns>
    public static List<T[]> GetPermutation(T[] t, int startIndex, int endIndex)
    {
    if (startIndex < 0 || endIndex > t.Length - 1)
    {
    return null;
    }
    List<T[]> list = new List<T[]>();
    GetPermutation(ref list, t, startIndex, endIndex);
    return list;
    }

    /// <summary>
    /// 返回数组所有元素的全排列
    /// </summary>
    /// <param name="t">所求数组</param>
    /// <returns>全排列的范型</returns>
    public static List<T[]> GetPermutation(T[] t)
    {
    return GetPermutation(t, 0, t.Length - 1);
    }

    /// <summary>
    /// 求数组中n个元素的排列
    /// </summary>
    /// <param name="t">所求数组</param>
    /// <param name="n">元素个数</param>
    /// <returns>数组中n个元素的排列</returns>
    public static List<T[]> GetPermutation(T[] t, int n)
    {
    if (n > t.Length)
    {
    return null;
    }
    List<T[]> list = new List<T[]>();
    List<T[]> c = GetCombination(t, n);
    for (int i = 0; i < c.Count; i++)
    {
    List<T[]> l = new List<T[]>();
    GetPermutation(ref l, c[i], 0, n - 1);
    list.AddRange(l);
    }
    return list;
    }


    /// <summary>
    /// 求数组中n个元素的组合
    /// </summary>
    /// <param name="t">所求数组</param>
    /// <param name="n">元素个数</param>
    /// <returns>数组中n个元素的组合的范型</returns>
    public static List<T[]> GetCombination(T[] t, int n)
    {
    if (t.Length < n)
    {
    return null;
    }
    int[] temp = new int[n];
    List<T[]> list = new List<T[]>();
    GetCombination(ref list, t, t.Length, n, temp, n);
    return list;
    }
    }
    }
    32 changes: 32 additions & 0 deletions Program.cs
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    using System;
    using System.Collections.Generic;
    using System.Text;

    namespace _4DigitalSolver
    {
    class Program
    {
    static void Main(string[] args)
    {
    Solver s = new Solver(4);
    while(s.Answers.Count > 1)
    {
    string i, a, b;
    Console.Write("Input=");
    i = Console.ReadLine();
    Console.Write("A=");
    a = Console.ReadLine();
    Console.Write("B=");
    b = Console.ReadLine();
    try
    {
    s.Filter(new Solver.Guess(i, int.Parse(a), int.Parse(b)));
    }
    catch (Exception e) { }

    Console.WriteLine("{0} remaining: {1}", s.Answers.Count, String.Join(", ", new List<string>(s.Answers).ToArray()));
    }
    Console.ReadKey();
    }
    }
    }
    76 changes: 76 additions & 0 deletions Solver.cs
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    using System;
    using System.Collections.Generic;
    using System.Text;
    using System.Text.RegularExpressions;

    namespace _4DigitalSolver
    {
    class Solver
    {
    public struct Guess
    {
    static Regex Duplicate = new Regex(@"(.).*\1");

    public string Value;
    public int A; public int B;

    public Guess(string value, int a, int b) { Value = value; A = a; B = b; }
    public Guess(string Answer, string Input)
    {
    if (Answer.Length != Input.Length) throw new ArgumentException("Misalign");

    Value = Input;
    if (Answer == Input)
    {
    A = Value.Length;
    B = 0;
    return;
    }

    if (Duplicate.Match(Input).Success) throw new ArgumentException("Dup");

    A = 0; B = 0;
    for (int i = 0; i < Answer.Length; i++)
    {
    int p = Answer.IndexOf(Input[i]);
    if (p == i) A++;
    else if (p != -1) B++;
    }
    }
    }
    List<string> answers;
    List<Guess> guesses = new List<Guess>();
    int length;

    public Solver(): this(4) {}
    public Solver(int length)
    {
    this.length = length;
    InitAnswer();
    }

    private void InitAnswer() {
    answers = new List<string>();

    var comb = new List<int[]>(PermutationAndCombination<int>.GetCombination(new int[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }, length));
    foreach(var c in comb) {
    var p = PermutationAndCombination<int>.GetPermutation(c);
    answers.AddRange(p.ConvertAll((i) => string.Join("", Array.ConvertAll(i, (j) => j.ToString()))));
    }
    }

    public void Filter(Guess guess)
    {
    guesses.Add(guess);

    answers.RemoveAll((string ans) =>
    {
    if (ans == guess.Value) return true;
    Guess g = new Guess(guess.Value, ans);
    return !(g.A == guess.A && g.B == guess.B);
    });
    }

    public System.Collections.ObjectModel.ReadOnlyCollection<string> Answers { get { return answers.AsReadOnly(); } }
    }
    }