HTMLify

func stringHash(s string, k int) string {
    var result string
    var chunk string
    for _, c := range s {
        chunk += string(c)
        if len(chunk) == k {
            var sum int
            for _, char := range chunk {
                sum += int(char) - 97
            }
            sum = sum % 26
            result += string(sum+97)
            chunk = ""
        }
    }
    return result
}