Incrementing alphabets

Question

I am trying to create a function which will give me alphabet position when an index is passed. It will be same like how excel shows it\'s columns. A...Z, AA,AB.... I wrote t

Answer 1

Any recursive function can be converted into an equivalent iterative one. I find it always easy to think recursively first:

static string GetColumnName(int index)
{
    const int alphabetsCount = 26;

    if (index > alphabetsCount) {
        return GetColumnName(index / alphabetsCount) + GetColumnName(index % alphabetsCount);
    } else {
        int code = (index - 1) + (int)'A';
        return char.ConvertFromUtf32(code);
    }
}

Which can be simple converted into:

static string GetColumnName(int index)
{
    const int alphabetsCount = 26;
    string result = string.Empty;

    while (index > 0) {
        result = char.ConvertFromUtf32(64 + (index % alphabetsCount)) + result;
        index /= alphabetsCount;
    }

    return result;
}

Even so, listen to Joel.