c# - 找出给定长度的所有可能单词的好方法是什么

Question

我正在尝试在 C# 中创建一个生成以下输出字符串的算法:

AAAA
AAAB
AAAC
...and so on...
ZZZX
ZZZY
ZZZZ

实现此目标的最佳方法是什么？

public static IEnumerable<string> GetWords()
{
    //Perform algorithm
    yield return word;
}

Answer 1

好吧，如果长度是常量 4，那么这将处理它:

public static IEnumerable<String> GetWords()
{
    for (Char c1 = 'A'; c1 <= 'Z'; c1++)
    {
        for (Char c2 = 'A'; c2 <= 'Z'; c2++)
        {
            for (Char c3 = 'A'; c3 <= 'Z'; c3++)
            {
                for (Char c4 = 'A'; c4 <= 'Z'; c4++)
                {
                    yield return "" + c1 + c2 + c3 + c4;
                }
            }
        }
    }
}

如果长度是一个参数，这个递归解决方案将处理它:

public static IEnumerable<String> GetWords(Int32 length)
{
    if (length <= 0)
        yield break;

    for (Char c = 'A'; c <= 'Z'; c++)
    {
        if (length > 1)
        {
            foreach (String restWord in GetWords(length - 1))
                yield return c + restWord;
        }
        else
            yield return "" + c;
    }
}