Bubble sorting?!

[m84uily]

The question is commented in the code so here it is:

code:

/* Question  The MEDIAN of an ordered set of numbers is the middle number if the set contains an odd number of elements.  It is the average of the two middle numbers if the set contains an  even number of elements.  Write a program to find the median of a set of numbers.  Start by making a list of random numbers.  Also choose the length of the list randomly.  Then sort it from largest to smallest.  Display the original list and the sorted list, side by side, as well as the median. */ var num, flag, temp, count, a, b, c, d, e, f, g, h, j, k : int count := 0 a := 0 b := 0 c := 0 d := 0 e := 0 f := 0 g := 0 h := 0 j := 0 k := 0 for i : 1 .. Rand.Int (1, 10)     count := count + 1     randint (num, 1, 9)     if count = 1 then         a := num     end if     if count = 2 then         b := num     end if     if count = 3 then         c := num     end if     if count = 4 then         d := num     end if     if count = 5 then         e := num     end if     if count = 6 then         f := num     end if     if count = 7 then         g := num     end if     if count = 8 then         h := num     end if     if count = 9 then         j := num     end if     if count = 10 then         k := num     end if end for var yes : array 1 .. count of int var random : boolean := true for last : 1 .. count %loops for the number of times the user specified     for i : 1 .. count - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if yes (i) > yes (i + 1) then %compares the first mark to the second mark             random := false %if the above statement is true the whole eqiuation is 'false' so it has to do it again, and again until it is 'true' so it ends             const temp := yes (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             yes (i) := yes (i + 1) %see above             yes (i + 1) := temp %see above         end if     end for     exit when random %exit when this statement is true end for

This is my first time using bubble sort and I'm really quite confused. I copied the bubble sort part from another post on the forums, and, not surprisingly it's not working out for me.

My first and foremost problem would be the error I get when I try to run this code " 'temp' has been previously declared" which I really don't know how to solve.

My second problem is, once I get bubble sort working I'm not entirely sure of how to display the numbers in the sorted order.

Thanks in advance and all help is very much appreciated.

[Insectoid]

What are the A, b, c, d, e... variables for?

the variable 'temp' is being declared more than once. You have

code:

var temp : int

in there more than once, or in a loop/conditional.

First, make an variable to hold the array length.

code:

var arrayLength : int := Rand.Int

Now, declare your array or random numbers.

code:

var bleh : array 1..arrayLength of int

Use a for loop to initialize the array

now, a bubble sort works like so.

code:

for x : 1..arrayLength     for y : 1..arrayLength - 1         if bleh (y) > bleh (y + 1) then             %swap bleh (y) with bleh (y+1)         end if     end for end for

then use a for loop to display the result!

You'll have to figure out the %swap part yourself.

[m84uily]

code:

var arrayLength : int := count var bleh : array 1 .. arrayLength of int for last : 1 .. arrayLength %loops for the number of times the user specified     for i : 1 .. arrayLength - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if bleh (i) > bleh (i + 1) then %compares the first mark to the second mark             random := false %if the above statement is true the whole eqiuation is 'false' so it has to do it again, and again until it is 'true' so it ends             const temp := bleh (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             bleh (i) := bleh (i + 1) %see above             bleh (i + 1) := temp %see above         end if     end for     exit when random %exit when this statement is true end for

I think I understand what you mean by swap, and I'm trying to use temp to do so. However at the line

code:

if bleh (i) > bleh (i + 1) then

I receive the error "Variable has no value"
How can I fix this?

Also! variables a - k are so I can work with them outside the for, because the question asks me to display the unordered numbers also.

[Tony]

start by fixing your variable names. Then actually assign some value to it.

[m84uily]

Quote:

start by fixing your variable names. Then actually assign some value to it.

Well, if by fixing variable names you mean, they're silly, then I understand, otherwise I don't really. Could you please expand a little more on this?

And I'd assumed I'd assigned a value to variable bleh in the lines:

code:

var arrayLength : int := count var bleh : array 1 .. arrayLength of int

and count is defined in the previous for statement in the lines:

code:

for i : 1 .. Rand.Int (1, 10)     count := count + 1     randint (num, 1, 9)

So, I'm not entirely sure where the missing value is, although I'm certain you're right as that is the problem.

Here is my code as a whole as it is now (including comments I have for myself):

code:

/* Question  The MEDIAN of an ordered set of numbers is the middle number if the set contains an odd number of elements.  It is the average of the two middle numbers if the set contains an  even number of elements.  Write a program to find the median of a set of numbers.  Start by making a list of random numbers.  Also choose the length of the list randomly.  Then sort it from largest to smallest.  Display the original list and the sorted list, side by side, as well as the median. */ var num, flag, count, a, b, c, d, e, f, g, h, j, k : int count := 0 a := 0 b := 0 c := 0 d := 0 e := 0 f := 0 g := 0 h := 0 j := 0 k := 0 for i : 1 .. Rand.Int (1, 10)     count := count + 1     randint (num, 1, 9)     if count = 1 then         a := num     end if     if count = 2 then         b := num     end if     if count = 3 then         c := num     end if     if count = 4 then         d := num     end if     if count = 5 then         e := num     end if     if count = 6 then         f := num     end if     if count = 7 then         g := num     end if     if count = 8 then         h := num     end if     if count = 9 then         j := num     end if     if count = 10 then         k := num     end if end for var arrayLength : int := count var bleh : array 1 .. arrayLength of int for last : 1 .. arrayLength %loops for the number of times the user specified     for i : 1 .. arrayLength - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if bleh (i) > bleh (i + 1) then %compares the first mark to the second mark             random := false %if the above statement is true the whole eqiuation is 'false' so it has to do it again, and again until it is 'true' so it ends             const temp := bleh (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             bleh (i) := bleh (i + 1) %see above             bleh (i + 1) := temp %see above         end if     end for     exit when random %exit when this statement is true end for /* **to display numbers in order they were randomized**  if count = 1 then  put a  end if  if count = 2 then  put a, " ", b  end if  if count = 3 then  put a, " " , b ," ",  c  end if  if count = 4 then  put a, " ",b, " ", c, " ", d  end if  if count = 5 then  put a, " ",b, " ", c, " ", d, " ", e  end if  if count = 6 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f  end if  if count = 7 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g  end if  if count = 8 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h  end if  if count = 9 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h, " ", j  end if  if count = 10 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h, " ", j, " ", k  end if  ==SORT METHODS==  BUBBLE SORT  loop  flag := 0  for i : 1 .. n - 1  if name ( i ) > name (i + 1) then  temp := name (i + 1)  name (i + 1) := name ( i )  name ( i ) := temp  flag := 1  end if  end for  exit when flag := 0  end loop VERY LONG IF STATEMENT SORT  if a > b and a > c and a > d and a > e and a >f and a > g and a > h and a > j and a > k then  a := a1  end if  if b > a and b > c and b > d and b > e and b > f and b >g and b > h and b > j and b > k  then  b := a1  end if  if c > a and c > b and c> d and c > e and c > f and c >g and c > h and c > j and c > k  then  c := a1  end if  if d > a and d > b and d> c and d > e and d > f and d >g and d > h and d > j and d > k  then  d := a1  end if  etc...  */

[Tony]

Yes, make your variable names meaningful. I don't know what you are talking about, when you use variable "bleh"

m84uily @ Tue Mar 10, 2009 5:36 pm wrote:

And I'd assumed I'd assigned a value to variable bleh in the lines:

code:

var arrayLength : int := count var bleh : array 1 .. arrayLength of int

What's the value of bleh(1) then?

[m84uily]

Tony @ Tue Mar 10, 2009 5:43 pm wrote:

Yes, make your variable names meaningful. I don't know what you are talking about, when you use variable "bleh"

m84uily @ Tue Mar 10, 2009 5:36 pm wrote:

And I'd assumed I'd assigned a value to variable bleh in the lines:

code:

var arrayLength : int := count var bleh : array 1 .. arrayLength of int

What's the value of bleh(1) then?

Thank you! I understand now. Heh, just took a simple question to make it click.

The sorter looks like this now:

code:

var arrayLength : int := count var bleh : array 1 .. arrayLength of int if count = 1 then     bleh (1) := a end if if count = 2 then     bleh (1) := a     bleh (2) := b end if if count = 3 then     bleh (1) := a     bleh (2) := b     bleh (3) := c end if if count = 4 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d end if if count = 5 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e end if if count = 6 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f end if if count = 7 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g end if if count = 8 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h end if if count = 9 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h     bleh (9) := j end if if count = 10 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h     bleh (9) := j     bleh (10) := k end if for last : 1 .. arrayLength %loops for the number of times the user specified     for i : 1 .. arrayLength - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if bleh (i) > bleh (i + 1) then %compares the first mark to the second mark             const temp := bleh (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             bleh (i) := bleh (i + 1) %see above             bleh (i + 1) := temp %see above         end if     end for end for

Which executes and such, although I'm not 100% it's working. I had to take out the random that use to be there, shown in the code here:

code:

var yes : array 1 .. count of int var random : boolean := true for last : 1 .. count %loops for the number of times the user specified     for i : 1 .. count - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if yes (i) > yes (i + 1) then %compares the first mark to the second mark             random := false %if the above statement is true the whole eqiuation is 'false' so it has to do it again, and again until it is 'true' so it ends             const temp := yes (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             yes (i) := yes (i + 1) %see above             yes (i + 1) := temp %see above         end if     end for     exit when random %exit when this statement is true end for

Whether or not it needs to be there I'm not sure. Ultimately, to decipher if it's working properly I need to know how to display the ordered results? (Don't worry, I'll change the variables at the end Tony )

[m84uily]

It can now execute with the random in it:

code:

/* Question  The MEDIAN of an ordered set of numbers is the middle number if the set contains an odd number of elements.  It is the average of the two middle numbers if the set contains an  even number of elements.  Write a program to find the median of a set of numbers.  Start by making a list of random numbers.  Also choose the length of the list randomly.  Then sort it from largest to smallest.  Display the original list and the sorted list, side by side, as well as the median. */ var num, flag, count, a, b, c, d, e, f, g, h, j, k : int count := 0 a := 0 b := 0 c := 0 d := 0 e := 0 f := 0 g := 0 h := 0 j := 0 k := 0 for i : 1 .. Rand.Int (1, 10)     count := count + 1     randint (num, 1, 9)     if count = 1 then         a := num     end if     if count = 2 then         b := num     end if     if count = 3 then         c := num     end if     if count = 4 then         d := num     end if     if count = 5 then         e := num     end if     if count = 6 then         f := num     end if     if count = 7 then         g := num     end if     if count = 8 then         h := num     end if     if count = 9 then         j := num     end if     if count = 10 then         k := num     end if end for var arrayLength : int := count var bleh : array 1 .. arrayLength of int if arrayLength = 1 then     bleh (1) := a end if if arrayLength = 2 then     bleh (1) := a     bleh (2) := b end if if arrayLength = 3 then     bleh (1) := a     bleh (2) := b     bleh (3) := c end if if arrayLength = 4 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d end if if arrayLength = 5 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e end if if arrayLength = 6 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f end if if arrayLength = 7 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g end if if arrayLength = 8 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h end if if arrayLength = 9 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h     bleh (9) := j end if if arrayLength = 10 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h     bleh (9) := j     bleh (10) := k end if var random : boolean := true for last : 1 .. arrayLength %loops for the number of times the user specified     for i : 1 .. arrayLength - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if bleh (i) > bleh (i + 1) then %compares the first mark to the second mark             random := false             const temp := bleh (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             bleh (i) := bleh (i + 1) %see above             bleh (i + 1) := temp %see above             exit when random = true         end if     end for end for /*  **to display numbers in order they were randomized**  if count = 1 then  put a  end if  if count = 2 then  put a, " ", b  end if  if count = 3 then  put a, " " , b ," ",  c  end if  if count = 4 then  put a, " ",b, " ", c, " ", d  end if  if count = 5 then  put a, " ",b, " ", c, " ", d, " ", e  end if  if count = 6 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f  end if  if count = 7 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g  end if  if count = 8 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h  end if  if count = 9 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h, " ", j  end if  if count = 10 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h, " ", j, " ", k  end if  ==SORT METHODS==  BUBBLE SORT  loop  flag := 0  for i : 1 .. n - 1  if name ( i ) > name (i + 1) then  temp := name (i + 1)  name (i + 1) := name ( i )  name ( i ) := temp  flag := 1  end if  end for  exit when flag := 0  end loop  VERY LONG IF STATEMENT SORT  if a > b and a > c and a > d and a > e and a >f and a > g and a > h and a > j and a > k then  a := a1  end if  if b > a and b > c and b > d and b > e and b > f and b >g and b > h and b > j and b > k  then  b := a1  end if  if c > a and c > b and c> d and c > e and c > f and c >g and c > h and c > j and c > k  then  c := a1  end if  if d > a and d > b and d> c and d > e and d > f and d >g and d > h and d > j and d > k  then  d := a1  end if  etc...  */

Still not sure how to display, though.

[m84uily]

HAH! Got it! Hail Satan!

Here's the nearly completed code (still need to change variables and do some other stuff the question asks of me) :

code:

/* Question  The MEDIAN of an ordered set of numbers is the middle number if the set contains an odd number of elements.  It is the average of the two middle numbers if the set contains an  even number of elements.  Write a program to find the median of a set of numbers.  Start by making a list of random numbers.  Also choose the length of the list randomly.  Then sort it from largest to smallest.  Display the original list and the sorted list, side by side, as well as the median. */ var num, flag, count, a, b, c, d, e, f, g, h, j, k : int count := 0 a := 0 b := 0 c := 0 d := 0 e := 0 f := 0 g := 0 h := 0 j := 0 k := 0 for i : 1 .. Rand.Int (1, 10)     count := count + 1     randint (num, 1, 9)     if count = 1 then         a := num     end if     if count = 2 then         b := num     end if     if count = 3 then         c := num     end if     if count = 4 then         d := num     end if     if count = 5 then         e := num     end if     if count = 6 then         f := num     end if     if count = 7 then         g := num     end if     if count = 8 then         h := num     end if     if count = 9 then         j := num     end if     if count = 10 then         k := num     end if end for var arrayLength : int := count var bleh : array 1 .. arrayLength of int if arrayLength = 1 then     bleh (1) := a end if if arrayLength = 2 then     bleh (1) := a     bleh (2) := b end if if arrayLength = 3 then     bleh (1) := a     bleh (2) := b     bleh (3) := c end if if arrayLength = 4 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d end if if arrayLength = 5 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e end if if arrayLength = 6 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f end if if arrayLength = 7 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g end if if arrayLength = 8 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h end if if arrayLength = 9 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h     bleh (9) := j end if if arrayLength = 10 then     bleh (1) := a     bleh (2) := b     bleh (3) := c     bleh (4) := d     bleh (5) := e     bleh (6) := f     bleh (7) := g     bleh (8) := h     bleh (9) := j     bleh (10) := k end if var random : boolean := true for last : 1 .. arrayLength %loops for the number of times the user specified     for i : 1 .. arrayLength - 1 %loops one less then user defined because its comaring #1 and #1+1, so it has to end at one less then usder defined because the program adds 1         if bleh (i) > bleh (i + 1) then %compares the first mark to the second mark             random := false             const temp := bleh (i) %here the two numbers are swamped so that #1 becomes #2, #2 becomes #1, using a tempoary variable to store the first number so itrs not overwrittem             bleh (i) := bleh (i + 1) %see above             bleh (i + 1) := temp %see above             exit when random = true         end if     end for end for for last : 1 .. arrayLength     put bleh (last) end for    /*  **to display numbers in order they were randomized**  if count = 1 then  put a  end if  if count = 2 then  put a, " ", b  end if  if count = 3 then  put a, " " , b ," ",  c  end if  if count = 4 then  put a, " ",b, " ", c, " ", d  end if  if count = 5 then  put a, " ",b, " ", c, " ", d, " ", e  end if  if count = 6 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f  end if  if count = 7 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g  end if  if count = 8 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h  end if  if count = 9 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h, " ", j  end if  if count = 10 then  put a, " ",b, " ", c, " ", d, " ", e, " ", f, " ",  g, " ", h, " ", j, " ", k  end if  ==SORT METHODS==  BUBBLE SORT  loop  flag := 0  for i : 1 .. n - 1  if name ( i ) > name (i + 1) then  temp := name (i + 1)  name (i + 1) := name ( i )  name ( i ) := temp  flag := 1  end if  end for  exit when flag := 0  end loop  VERY LONG IF STATEMENT SORT  if a > b and a > c and a > d and a > e and a >f and a > g and a > h and a > j and a > k then  a := a1  end if  if b > a and b > c and b > d and b > e and b > f and b >g and b > h and b > j and b > k  then  b := a1  end if  if c > a and c > b and c> d and c > e and c > f and c >g and c > h and c > j and c > k  then  c := a1  end if  if d > a and d > b and d> c and d > e and d > f and d >g and d > h and d > j and d > k  then  d := a1  end if  etc...  */

[Tony]

I'm not quite sure -- what are you trying to display (and where, in your program, would that data be found)?

[Insectoid]

To display the list in original order, just us a for loop and put statements before you sort it.

[Tallguy]

check this topic out, it may help

http://compsci.ca/v3/viewtopic.php?t=20423