When reading from a file and then sorting, are u supposed to enter a few dummy values?
What i mean to say is, if i have to read a file into a linked list and then sort the file based on certain criteria, do i have to make dummy values to initialise the list?
Your question is not at all clear...
Still, most probably the answer is no. Why would need any dummy values ? Where'd you get that idea ?
Last edited by Zeeshan; 06-04-2002 at 11:01 PM.
I've seen a sample program where a file has to bve read into a linked list and the programmer used dummy values and i just wanted to know if they were necessary or not. I guess that its not a big thing but if anyone does know anything reply
I just tried the code without a dummy value and i got a segmenatio fault. I guess that u do need to have dummy values of some sort.
What are these dummy values and where are you using them???
these dummy values go something like this...
Lets say i want to read in a file with this format
"number name rate"
then a procedure just initialises this list by adding dummy values like:
"-1" "" "0.0"
This is done before the file is actually read in to the linked list. I beleive that it is done to initialise the linked list
Sometimes a dummy node is put in front of a list. This is to prevent from having an empty list and it can be useful having a fixed root. For example when sorting the list and the first node must be replaced. When having a fixed root, it is the second note and you can keep the root-pointer to just the first node.
>When reading from a file and then sorting, are u supposed to
>enter a few dummy values?
No, that is not necessary.
>I just tried the code without a dummy value and i got a
>segmenatio fault. I guess that u do need to have dummy values
>of some sort.
I think it is implementation dependent. If the program expects dummy initialisation values, then it might crash or exit if it doesn't find it. Take a look at how the list is initialised and how initialisation is related to the file. I think that will provide the answer.
