Hey there,

I know you guys cant help when it comes to homework, so im kind of stuck. I need to make a c++ program that will sort a doubly linked like in decsending order and im not sure where to start. So maybe if someone could even just write a simple algorithm to give me a guide line?? or something like that, it would be very much appreciated.

Thank you

A doubly linked list containing what data type? Your sort algorithm is largely dependent on the data type stored in the list. Basically, you just implement the necessary features of the list for basic list management. Then, you enable your sort routine using iteration and list management functions.


:davis:

The data type would be integers....

Hey guys this what ive done for an algorithm to sort in descending order a doubly linked list. Dont know if its right completly, so if anyone can please point out anything they think is wrong

Thank You


BEGIN sortDoubleLink (PList, POne)
SET min to integer
SET array [1…n]
IF (PList not null)
SET min to PList -> data
SET POne to PList -> Link
WHILE (POne not null)
IF (POne < next data)
SET POne to PList
SET PList -> Link
ELSE INCREMENT to next array
ENDWHILE
ENDIF
RETURN (list)
END sortDoubleLink

search google for

probably 1 of these bubblesort, quicksort, mergesort algorithm.

When you say doubly linked list do you mean like a binary tree or a linear double linked list with current pointing to next and previous?


[leftlink][data][rightlink] - > [leftlink][data][rightlink] - > [leftlink][data][rightlink]

or
________________[leftlink][data][rightlink]
_______________ /___________________\
[leftlink][data][rightlink]________________[leftlink][data][rightlink]

excuse my attempt at drawing?

Here is another algorithm that needs checking

here is the question:

Please write a non-recursive algorithm in pseudo code to solve the above problem using
stacks. The algorithm receives the following parameters: a two-dimensional array maze
(indexed from [1, 1]) that represents the maze, an integer N, where N > 0, which is the
size of the maze (hence, the array has valid elements from maze[1, 1] to maze[N, N]),
two integers (m1, m2) that are the coordinates of the starting point of the mouse (e.g.,
(m1=2, m2=1) means the starting point is row 2, column 1), and two integers (e1, e2) that
are the coordinates of the exist. For example, to represent the following figure (where the
shaded cells represent the wall), we have maze[1, 1] = 1, maze[1, 2] = 1, maze[1, 3] = 1,
maze[2, 1] = 0, maze[2, 2] = 1, maze[2, 3] = 0, maze[3, 1] = 0, maze[3, 2] = 0, maze[3, 3]
= 0; m1=2, m2=1, e1=2, e2=3.


here is the algorithm i have written


BEGIN mouseMaze
SET starting point (m1=2, m2=1)
SET exit (e1=2, e2=3)
WHILE (mouse = starting point)
move mouse (m1=1, m2=1) THEN
move mouse (m1=1, m2=2) & (m1=1, m2=3) THEN
exit maze if exit found
IF not exit
PRINT “(1, 1), (1, 2), (1, 3), (2, 3)”
ELSE
RETURN to start point
ENDIF
ENDWHILE
WHILE (mouse = starting point)
move mouse (m1=2, m2=2) THEN
exit maze if exit found
IF maze empty
PRINT “(2, 2), (2, 3)
ELSE
RETURN to start point
ENDIF
ENDWHILE
WHILE (mouse = starting point)
move mouse (m1=3, m2=1) THEN
move mouse (m1=3, m2=2) & (m1=3, m2=3) THEN
exit maze
IF not exit
PRINT “(3, 1), (3, 2), (3, 3), (2, 3)”
ELSE
RETURN to start point
ENDIF
ENDWHILE
END mouseMaze

i mean linear double linked list with current pointing to next and previous. Ive attempted a algorithm in the new post a few posts above this, dont know if its right tho...

I have merged that thread with this one - you will find it as post #4 in this thread.

Please don't double post on the same problem. It makes it difficult for the people offering help to do so, as I think you might find happened in this case (since they couldn't see the algorithm you came up with). A more suggestive thread name would be helpful too.

I ask you to please try and read the "Guidelines for posting requests for help" (the link is in my signature), in order to help us help you.

I wish you happy learning.

Best regards,
Lucian

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I have merged the new thread you started too... please post the next related issue in the same thread.
I am not sure how the software used for merging threads works (it porbably orders posts by date), but this post was merged as post #6 in this thread.

__________________
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