[Solved] Does there exist an algorithm for iterating through all strings that conform to a particular regex?

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Let’s say the domain is as following

String domain[] = { a, b, .., z, A, B, .. Z, 0, 1, 2, .. 9 };

Let’s say the password size is 8

ArrayList allCombinations = getAllPossibleStrings2(domain,8);

This is going to generate SIZE(domain) * LENGTH number of combinations, which is in this example (26+26+10)^8 = 62^8 = 218,340,105,584,896 combinations

Then you can enumerate all possible string up\at to a specific size like this

// get all possible combinations up to a given size
static ArrayList getAllPossibleStrings1(ArrayList domain, int maxSize)
{
    ArrayList list = new ArrayList();
    int i = 1;

    list.AddRange(domain);

    while(++i <= maxSize)
        for(String a in list)
            for(String b in domain)
                list.Add(String.Concat(a,b));

    return list;
}

// get all possible combinations at a given size
static ArrayList getAllPossibleStrings2(ArrayList domain, int size)
{
    ArrayList list = new ArrayList();
    ArrayList temp = new ArrayList();
    int i = 1;

    list.AddRange(domain);

    while(++i <= maxSize)
    {
        for(String a in list)
            for(String b in domain)
                temp.Add(String.Concat(a,b));

        list.Clear();
        list.AddRange(temp);
        temp.Clear();
    }

    return list;
}

solved Does there exist an algorithm for iterating through all strings that conform to a particular regex?