Reverse split a big number

rev_split_num.rb

def log(what, str, offset=0)
  len = str.length
  puts sprintf("| %-25s | %30s | (%-2s) |", what, str << " "*offset, len)
  puts "_____________________________________________________________________"
end

def doit(match, buffer_size)
  sl = match.slice(-14, 14)
  log "14 of first 16", sl, buffer_size
  
  sl = match.slice(-15, 15)
  log "15 of first 16", sl, buffer_size
  
  sl = match.slice(-16, 16)
  log "16 of first 16", sl, buffer_size
end

original = "12345678901234567890123456"
log "Original", original
copy = original.dup

copy.length

for i in 0..copy.length - 16
  sl = copy.slice((-16 + -i), 16)
  doit(sl, i)
end