HTMLify

func convertToTitle(columnNumber int) string {
    var bs []int
    for ;columnNumber!=0; {
        d := columnNumber%26
        if d == 0 {
            d = 26
            columnNumber--
        }
        bs = append(bs, d)
        columnNumber /= 26
    }
    title := ""
    for _, d := range bs {
        title = string(rune(d+64)) + title
    }
    return title
}