i can use an int as the first field, there are four different combinations so i can use the first two bits, if the bit is 0 then the optional field is not there, if its 1 then it is. so 01 means the weight is there but the firstname is not
Now the challenge. Devise method for storing the list of fields that are present and are missing. Store this information in the first few bytes of the line (before the lastname field), using as few bytes as possible (hint: use binary bits, with 1 meaning field present, 0 meaning field not present). Use this map the parse the data. Understand what I'm waffling about?