Linked Lists

El_Presidente

Ok then big brainy programmer types.

I'm trying to get my head around linked lists and have a class called Element which holds and interger and a refernce to to the next elemnt.

Could anyone give me the code to use this to construct a linked list of integers and then dup this information into an array?

And no, I'm not cheating on any college work, this is just for my own interest.

spod

what language, and any chance of letting us see the class? or are at least the interface details?

It should make it alot easier to whip together the necessary code..

El_Presidente

Java

public class Element(int value, Element next)

Baz_

hmmmmmmmm, don't know java, but at last there is a good programming question on the board.

Cerberus

It is easy enough to do in C++ (a bit messy though) so I imagine it should be a hell of a lot easier and more straight forward in Java given all the fancy memory management stuff I heard it has. Come on Javamen, show us what your made of and help El_P!!

El_Presidente

Yes indeed, lets all pool are collective programming abilities together and help El_Pres!

quozl

This is all done off the top of my head without rereading, so expect typos/wrong variable names, and it not to compile. But this is the code you want for C. If you know some java should be easy to translate.


struct element{
int value;
element *next_element;
}

void main(){
element first, current;
first->next_element=NULL;
first.value=10;
current=first;

}

// to find one in particular given a
// value //to find
element *findit(int value, element *first){
element *loop;
loop=first;
while (loop) { //if not NULL
if (loop.value == value)
return &loop;
loop=loop->next; // next in list
}
return (NULL);
}

void add_one(int value, element *first){
element *loop, *new;
loop=first;
new.value=value;
if (!loop){
printf("Empty list, bold.\n\r");
return;
}
while (loop->next) //long as more
loop=loop->next
loop->next=new; //append new element
return;
}

to dump into array just iterate through the list, counting elements, then malloc (memory allocate) the correct size array. SImpler in java I think.
to copy code use something like
(assumning my_array[?] is global and right size from above)

void dump(element *first){
element *loop=first;
int i=0; //arrays start at 0
while (loop){
my_array=loop.value;
loop=loop->next;
i++;
}
}
this doesnt check for array overruns so make sure you have already made correct size array or instead resize array on the fly.

spod

gah busy atm.

if i get a chance I'ill do up something over weekend.

How's that?

ps. java, om nyomgh.

doon

Here is a link to a sample linked list written in java. http://www.cs.waikato.ac.nz/~312/lectures/lecture2/sld001.htm

What you should use is the Vector class in java.util. I does all the stuff you can do with a linked list.
doon.