C# - 演算子のオーバーロード、インデクサー、プロパティ(集合クラスの定義と部分集合、和集合、対称差)

開発環境

• Microsoft Windows 7 Home Premium (OS)
• Microsoft Visual C# 2010 Express Edition (IDE)
• 言語: C#

独習C# 第3版　ハーバート・シルト (著) エディフィストラーニング株式会社 矢嶋聡 (監修, 翻訳) の第7章(C演算子のオーバーロード、インデクサー、プロパティ)の理解度チェック10、11、12を解いてみる。

10, 11, 12.

コード

using System;

public class Set
{
    char[] members;
    public int Length { get; private set; }
    public Set()
    {
        Length = 0;
    }
    public Set(int size)
    {
        members = new char[size];
        Length = 0;
    }
    public Set(Set s)
    {
        members = new char[s.Length];
        for (int i = 0; i < s.Length; i++)
        {
            members[i] = s[i];
        }
        Length = s.Length;
    }
    public char this[int idx]
    {
        get
        {
            if (idx >= 0 && idx < Length)
            {
                return members[idx];
            }
            else
            {
                return (char)0;
            }
        }
    }
    int find(char ch)
    {
        for (int i = 0; i < Length; i++)
        {
            if (members[i] == ch)
            {
                return i;
            }
        }
        return -1;
    }
    public static Set operator +(Set ob, char ch)
    {
        if (ob.find(ch) != -1)
        {
            return new Set(ob);
        }
        else
        {
            Set newset = new Set(ob.Length + 1);
            for (int i = 0; i < ob.Length; i++)
            {
                newset.members[i] = ob.members[i];
            }
            newset.Length = ob.Length + 1;
            newset.members[newset.Length - 1] = ch;
            return newset;
        }
    }
    public static Set operator -(Set ob, char ch)
    {
        Set newset = new Set();
        int i = ob.find(ch);
        for (int j = 0; j < ob.Length; j++)
        {
            if (j != i)
            {
                newset = newset + ob.members[j];
            }
        }
        return newset;
    }
    public static Set operator +(Set ob1, Set ob2)
    {
        Set newset = new Set(ob1);
        for (int i = 0; i < ob2.Length; i++)
        {
            newset = newset + ob2[i];
        }
        return newset;
    }
    public static Set operator -(Set ob1, Set ob2)
    {
        Set newset = new Set(ob1);
        for (int i = 0; i < ob2.Length; i++)
        {
            newset -= ob2[i];
        }
        return newset;
    }
    public static bool operator <(Set ob1, Set ob2)
    {
        for (int i = 0; i < ob1.Length; i++)
        {
            if (ob2.find(ob1[i]) == -1)
            {
                return false;
            }
        }
        return true;
    }
    public static bool operator >(Set ob1, Set ob2)
    {
        for (int i = 0; i < ob2.Length; i++)
        {
            if (ob1.find(ob2[i]) == -1)
            {
                return false;
            }
        }
        return true;
    }
    public static Set operator &(Set ob1, Set ob2)
    {
        Set newset = new Set();
        for (int i = 0; i < ob2.Length; i++)
        {
            if (ob1.find(ob2[i]) != -1)
            {
                newset += ob2[i];
            }
        }
        return newset;
    }
    public static Set operator |(Set ob1, Set ob2)
    {
        return (ob1 + ob2) - (ob1 & ob2);
    }
    public static void Display(Set set)
    {
        for (int i = 0; i < set.Length; i++)
        {
            Console.Write("{0} ", set[i]);
        }
        Console.WriteLine();
    }
}
class Tester
{
    public void Run()
    {
        Set s1 = new Set();
        Set s2 = new Set();
        Set s3 = new Set();
        s1 += 'a';
        s1 += 'b';
        s1 += 'c';
        s2 += 'a';
        s2 += 'b';
        s3 += 'b';
        s3 += 'c';
        s3 += 'd';
        s3 += 'e';
        Set[] sets = { s1, s2, s3 };
        for (int i = 0; i < sets.Length; i++)
        {
            Console.Write("s{0}: ", i + 1);
            Set.Display(sets[i]);
        }
        Console.WriteLine("s1s2:{1}", 
            s1 < s2, s1 > s2);
        Console.Write("s1 & s2: ");
        Set.Display(s1 & s2);
        Console.Write("s1 & s3: ");
        Set.Display(s1 & s3);
        Console.Write("s1 | s2: ");
        Set.Display(s1 | s2);
        Console.Write("s1 | s3: ");
        Set.Display(s1 | s3);
    }
    static void Main()
    {
        Tester t = new Tester();
        t.Run();
    }
}

入出力結果(Console Window)

s1: a b c
s2: a b
s3: b c d e
s1<s2: False, s1>s2:True
s1 & s2: a b
s1 & s3: b c
s1 | s2: c
s1 | s3: a d e
続行するには何かキーを押してください . . .