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largest no
how can i pick up largest no from 5 rows by 5 column matrix????
how can i pick up largest no from 5 rows by 5 column matrix????
<bele_harshad2@yahoo.co.in> schrieb im Newsbeitrag news:1181123442.757983.117760@x35g2000prf.googlegroups.com... > how can i pick up largest no from 5 rows by 5 column matrix????
By copmaring the first with the send, then the larted of that comparisn with the 3rd, the larger of that with the 4th and so on until the 25th Bye, Jojo
<bele_harshad2@yahoo.co.in> schrieb im Newsbeitrag news:1181123486.285232.125040@q19g2000prn.googlegroups.com... > how can i pick up largest no from 5 rows by 5 column matrix????
Yes, we got it the 1st time already...
On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: > how can i pick up largest no from 5 rows by 5 column matrix????
Step 1. Sort the columns of each row into ascending order. Step 2. Sort the rows into ascending order using the last column as the key. Step 3. Pick the last column of the last row.
mark_blue@pobox.com said: > On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >> how can i pick up largest no from 5 rows by 5 column matrix???? > Step 1. Sort the columns of each row into ascending order. > Step 2. Sort the rows into ascending order using the last column as > the key. > Step 3. Pick the last column of the last row.
I'm sure we can do better than O(c log c + r log r). Perhaps we should specify a particular sort. That can get us right up to O(c^2 + r^2) without any major effort. But can anyone find an exponential-time algorithm? -- Richard Heathfield "Usenet is a strange place" - dmr 29/7/1999 http://www.cpax.org.uk email: rjh at the above domain, - www.
On 6 Jun, 11:29, Richard Heathfield <r@see.sig.invalid> wrote: > mark_blue @pobox.com said: > > On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: > >> how can i pick up largest no from 5 rows by 5 column matrix???? > > Step 1. Sort the columns of each row into ascending order. > > Step 2. Sort the rows into ascending order using the last column as > > the key. > > Step 3. Pick the last column of the last row. > I'm sure we can do better than O(c log c + r log r). Perhaps we should > specify a particular sort. That can get us right up to O(c^2 + r^2) > without any major effort. But can anyone find an exponential-time > algorithm?
There's a big problem here, though - how can we sort anything when we don't know how to tell whether one thing is larger than another?
<mark_blue@pobox.com> schrieb im Newsbeitrag news:1181128492.399756.63130@o5g2000hsb.googlegroups.com...
> On 6 Jun, 11:29, Richard Heathfield <r @see.sig.invalid> wrote: >> mark_blue @pobox.com said: >> > On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: >> >> how can i pick up largest no from 5 rows by 5 column matrix???? >> > Step 1. Sort the columns of each row into ascending order. >> > Step 2. Sort the rows into ascending order using the last column as >> > the key. >> > Step 3. Pick the last column of the last row. >> I'm sure we can do better than O(c log c + r log r). Perhaps we should >> specify a particular sort. That can get us right up to O(c^2 + r^2) >> without any major effort. But can anyone find an exponential-time >> algorithm? > There's a big problem here, though - how can we sort anything when we > don't know how to tell whether one thing is larger than another?
Hmm, the OP talked abut 'no' wich I assume to mean 'number', so it probably is some integral or floating point number, which are fairly easy to find the larger. Bye, Jojo
On 6 Jun, 12:25, "Joachim Schmitz" <nospam.j@schmitz-digital.de> wrote:
> <mark_blue @pobox.com> schrieb im Newsbeitrag news:1181128492.399756.63130@o5g2000hsb.googlegroups.com... > > On 6 Jun, 11:29, Richard Heathfield <r@see.sig.invalid> wrote: > >> mark_blue@pobox.com said: > >> > On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: > >> >> how can i pick up largest no from 5 rows by 5 column matrix???? > >> > Step 1. Sort the columns of each row into ascending order. > >> > Step 2. Sort the rows into ascending order using the last column as > >> > the key. > >> > Step 3. Pick the last column of the last row. > >> I'm sure we can do better than O(c log c + r log r). Perhaps we should > >> specify a particular sort. That can get us right up to O(c^2 + r^2) > >> without any major effort. But can anyone find an exponential-time > >> algorithm? > > There's a big problem here, though - how can we sort anything when we > > don't know how to tell whether one thing is larger than another? > Hmm, the OP talked abut 'no' wich I assume to mean 'number', so it probably > is some integral or floating point number, which are fairly easy to find the > larger.
Finding the largest value in some set is a trivial extension of finding which of two values is the larger - if the OP wanted us to write code to do the former, it implies they probably can't do the latter...
<mark_blue@pobox.com> schrieb im Newsbeitrag news:1181129890.964660.56020@p47g2000hsd.googlegroups.com...
> On 6 Jun, 12:25, "Joachim Schmitz" <nospam.j @schmitz-digital.de> > wrote: >> <mark_blue @pobox.com> schrieb im >> Newsbeitrag news:1181128492.399756.63130@o5g2000hsb.googlegroups.com... >> > On 6 Jun, 11:29, Richard Heathfield <r@see.sig.invalid> wrote: >> >> mark_blue@pobox.com said: >> >> > On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: >> >> >> how can i pick up largest no from 5 rows by 5 column matrix???? >> >> > Step 1. Sort the columns of each row into ascending order. >> >> > Step 2. Sort the rows into ascending order using the last column as >> >> > the key. >> >> > Step 3. Pick the last column of the last row. >> >> I'm sure we can do better than O(c log c + r log r). Perhaps we should >> >> specify a particular sort. That can get us right up to O(c^2 + r^2) >> >> without any major effort. But can anyone find an exponential-time >> >> algorithm? >> > There's a big problem here, though - how can we sort anything when we >> > don't know how to tell whether one thing is larger than another? >> Hmm, the OP talked abut 'no' wich I assume to mean 'number', so it >> probably >> is some integral or floating point number, which are fairly easy to find >> the >> larger. > Finding the largest value in some set is a trivial extension of > finding which of two values is the larger - if the OP wanted us to > write code to do the former, it implies they probably can't do the > latter...
To me it sounds like a homework assignment...
Joachim Schmitz wrote: > <mark_blue @pobox.com> schrieb im Newsbeitrag ... snip ... >> Finding the largest value in some set is a trivial extension of >> finding which of two values is the larger - if the OP wanted us >> to write code to do the former, it implies they probably can't >> do the latter... > To me it sounds like a homework assignment...
No! I can't imagine a student trying to pull such a scurvy trick. Couldn't possibly be true! -- <http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt> <http://www.securityfocus.com/columnists/423> <http://www.aaxnet.com/editor/edit043.html> <http://kadaitcha.cx/vista/dogsbreakfast/index.html> cbfalconer at maineline dot net -- Posted via a free Usenet account from http://www.teranews.com
mark_blue @pobox.com wrote: > Richard Heathfield <r @see.sig.invalid> wrote: >> mark_blue @pobox.com said: >>> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>>> how can i pick up largest no from 5 rows by 5 column matrix???? >>> Step 1. Sort the columns of each row into ascending order. >>> Step 2. Sort the rows into ascending order using the last column as >>> the key. >>> Step 3. Pick the last column of the last row. >> I'm sure we can do better than O(c log c + r log r). Perhaps we >> should specify a particular sort. That can get us right up to >> O(c^2 + r^2) without any major effort. But can anyone find an >> exponential-time algorithm? > There's a big problem here, though - how can we sort anything when > we don't know how to tell whether one thing is larger than another?
You apparantly totally missed the humor involved in RH's post. -- <http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt> <http://www.securityfocus.com/columnists/423> <http://www.aaxnet.com/editor/edit043.html> <http://kadaitcha.cx/vista/dogsbreakfast/index.html> cbfalconer at maineline dot net -- Posted via a free Usenet account from http://www.teranews.com
"CBFalconer" <cbfalco@yahoo.com> schrieb im Newsbeitrag news:4666D14E.D9A3A057@yahoo.com...
> mark_blue @pobox.com wrote: >> Richard Heathfield <r @see.sig.invalid> wrote: >>> mark_blue @pobox.com said: >>>> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>>>> how can i pick up largest no from 5 rows by 5 column matrix???? >>>> Step 1. Sort the columns of each row into ascending order. >>>> Step 2. Sort the rows into ascending order using the last column as >>>> the key. >>>> Step 3. Pick the last column of the last row. >>> I'm sure we can do better than O(c log c + r log r). Perhaps we >>> should specify a particular sort. That can get us right up to >>> O(c^2 + r^2) without any major effort. But can anyone find an >>> exponential-time algorithm? >> There's a big problem here, though - how can we sort anything when >> we don't know how to tell whether one thing is larger than another? > You apparantly totally missed the humor involved in RH's post.
Me too I must admit. Isn't that what smileys have been invented for? Bye, Jojo
Richard Heathfield <r @see.sig.invalid> writes: > mark_blue @pobox.com said: >> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>> how can i pick up largest no from 5 rows by 5 column matrix???? >> Step 1. Sort the columns of each row into ascending order. >> Step 2. Sort the rows into ascending order using the last column as >> the key. >> Step 3. Pick the last column of the last row. > I'm sure we can do better than O(c log c + r log r). Perhaps we should > specify a particular sort. That can get us right up to O(c^2 + r^2) > without any major effort. But can anyone find an exponential-time > algorithm?
Google "permutation sort". -- Keith Thompson (The_Other_Keith) k@mib.org <http://www.ghoti.net/~kst> San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst> "We must do something. This is something. Therefore, we must do this." -- Antony Jay and Jonathan Lynn, "Yes Minister"
On 06/06/2007 18:29, Joachim Schmitz wrote:
> "CBFalconer" <cbfalco @yahoo.com> schrieb im Newsbeitrag > news:4666D14E.D9A3A057@yahoo.com... >> mark_blue @pobox.com wrote: >>> Richard Heathfield <r @see.sig.invalid> wrote: >>>> mark_blue @pobox.com said: >>>>> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>>>>> how can i pick up largest no from 5 rows by 5 column matrix???? >>>>> Step 1. Sort the columns of each row into ascending order. >>>>> Step 2. Sort the rows into ascending order using the last column as >>>>> the key. >>>>> Step 3. Pick the last column of the last row. >>>> I'm sure we can do better than O(c log c + r log r). Perhaps we >>>> should specify a particular sort. That can get us right up to >>>> O(c^2 + r^2) without any major effort. But can anyone find an >>>> exponential-time algorithm? >>> There's a big problem here, though - how can we sort anything when >>> we don't know how to tell whether one thing is larger than another? >> You apparantly totally missed the humor involved in RH's post. > Me too I must admit. Isn't that what smileys have been invented for?
A smiley would ruin the joke considerably, I must say. -- Denis Kasak
Richard Heathfield wrote: > mark_blue @pobox.com said: >> On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: >>> how can i pick up largest no from 5 rows by 5 column matrix???? > I'm sure we can do better than O(c log c + r log r). Perhaps we should > specify a particular sort. That can get us right up to O(c^2 + r^2) > without any major effort. But can anyone find an exponential-time > algorithm?
Arrgh.. exponential-time??! The worst sorting algorithms I know, are O(N^2). :-/ I can't remember Knuth or Sedgewick, discussing anything worse than that. Give a hint please.. -- Tor <torust [at] online [dot] no>
Tor Rustad said:
> Richard Heathfield wrote: >> mark_blue@pobox.com said: >>> On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: >>>> how can i pick up largest no from 5 rows by 5 column matrix???? >> I'm sure we can do better than O(c log c + r log r). Perhaps we >> should specify a particular sort. That can get us right up to O(c^2 + >> r^2) without any major effort. But can anyone find an >> exponential-time algorithm? > Arrgh.. exponential-time??! The worst sorting algorithms I know, are > O(N^2). :-/ > I can't remember Knuth or Sedgewick, discussing anything worse than > that. > Give a hint please..
Well, let's see now... while not sorted exchange two elements at random endwhile That would do it, I think. -- Richard Heathfield "Usenet is a strange place" - dmr 29/7/1999 http://www.cpax.org.uk email: rjh at the above domain, - www.
Keith Thompson <k @mib.org> writes: > Richard Heathfield <r @see.sig.invalid> writes: >> mark_blue @pobox.com said: >>> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>>> how can i pick up largest no from 5 rows by 5 column matrix???? >>> Step 1. Sort the columns of each row into ascending order. >>> Step 2. Sort the rows into ascending order using the last column as >>> the key. >>> Step 3. Pick the last column of the last row. >> I'm sure we can do better than O(c log c + r log r). Perhaps we should >> specify a particular sort. That can get us right up to O(c^2 + r^2) >> without any major effort. But can anyone find an exponential-time >> algorithm? > Google "permutation sort".
Sorry, permutation sort isn't exponential-time. (It's worse.) -- Keith Thompson (The_Other_Keith) k@mib.org <http://www.ghoti.net/~kst> San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst> "We must do something. This is something. Therefore, we must do this." -- Antony Jay and Jonathan Lynn, "Yes Minister"
bele_harshad2 @yahoo.co.in wrote: > how can i pick up largest no from 5 rows by 5 column matrix???? No matrices in C, sorry. We do have arrays though. Consider.. int arr[5][5]; Does this satisfy your description of a matrix? The arr array has 25 elements. We can find the largest of them by simply tripping through the array comparing 'this' one to the previously larger one. The position of the largest element in the array might also be of interest. Consider.. int i, j, r, c, max = 0; for (i = 0; i < 5; ++i) for (j = 0; j < 5; ++j) if (arr[i][j] > max) { max = arr[i][j]; r = i, c = j; } When this finishes, max will hold the largest int and r and c will tell you where it is. And very quickly. -- Joe Wright "Everything should be made as simple as possible, but not simpler." --- Albert Einstein ---
Richard Heathfield <r @see.sig.invalid> writes: > Tor Rustad said: >> Richard Heathfield wrote: >>> mark_blue @pobox.com said: >>>> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>>>> how can i pick up largest no from 5 rows by 5 column matrix???? >>> I'm sure we can do better than O(c log c + r log r). Perhaps we >>> should specify a particular sort. That can get us right up to O(c^2 + >>> r^2) without any major effort. But can anyone find an >>> exponential-time algorithm? >> Arrgh.. exponential-time??! The worst sorting algorithms I know, are >> O(N^2). :-/ >> I can't remember Knuth or Sedgewick, discussing anything worse than >> that. >> Give a hint please.. > Well, let's see now... > while not sorted > exchange two elements at random > endwhile > That would do it, I think.
If the exchanges are truly random, that's not guaranteed to terminate, so it doesn't qualify as an algorithm. -- Keith Thompson (The_Other_Keith) k@mib.org <http://www.ghoti.net/~kst> San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst> "We must do something. This is something. Therefore, we must do this." -- Antony Jay and Jonathan Lynn, "Yes Minister"
Tor Rustad wrote: > Richard Heathfield wrote: >> mark_blue @pobox.com said: >>> On 6 Jun, 10:50, bele_harshad2 @yahoo.co.in wrote: >>>> how can i pick up largest no from 5 rows by 5 column matrix??? >> I'm sure we can do better than O(c log c + r log r). Perhaps we >> should specify a particular sort. That can get us right up to >> O(c^2 + r^2) without any major effort. But can anyone find an >> exponential-time algorithm? > Arrgh.. exponential-time??! The worst sorting algorithms I know, > are O(N^2). :-/ > I can't remember Knuth or Sedgewick, discussing anything worse > than that. > Give a hint please..
I don't know the O(), but try simply rearranging the sortee at random, then check if sorted. If not, repeat. -- <http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt> <http://www.securityfocus.com/columnists/423> <http://www.aaxnet.com/editor/edit043.html> <http://kadaitcha.cx/vista/dogsbreakfast/index.html> cbfalconer at maineline dot net -- Posted via a free Usenet account from http://www.teranews.com
Keith Thompson wrote: > Richard Heathfield <r @see.sig.invalid> writes: >> Tor Rustad said: ... snip ... >>> Arrgh.. exponential-time??! The worst sorting algorithms I know, >>> are O(N^2). :-/ >>> I can't remember Knuth or Sedgewick, discussing anything worse >>> than that. >>> Give a hint please.. >> Well, let's see now... >> while not sorted >> exchange two elements at random >> endwhile >> That would do it, I think. > If the exchanges are truly random, that's not guaranteed to > terminate, so it doesn't qualify as an algorithm.
Yes it is, given sufficient time and a really random generator :-) -- <http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt> <http://www.securityfocus.com/columnists/423> <http://www.aaxnet.com/editor/edit043.html> <http://kadaitcha.cx/vista/dogsbreakfast/index.html> cbfalconer at maineline dot net -- Posted via a free Usenet account from http://www.teranews.com
CBFalconer <cbfalco @yahoo.com> writes: > Keith Thompson wrote: >> Richard Heathfield <r @see.sig.invalid> writes: >>> Tor Rustad said: > ... snip ... >>>> Arrgh.. exponential-time??! The worst sorting algorithms I know, >>>> are O(N^2). :-/ >>>> I can't remember Knuth or Sedgewick, discussing anything worse >>>> than that. >>>> Give a hint please.. >>> Well, let's see now... >>> while not sorted >>> exchange two elements at random >>> endwhile >>> That would do it, I think. >> If the exchanges are truly random, that's not guaranteed to >> terminate, so it doesn't qualify as an algorithm. > Yes it is, given sufficient time and a really random generator :-)
No, it's not. A truly random generator can generate any possible sequence, including a sequence that causes the code to repeatedly swap the first two elements forever. The worst-case behavior is that it never terminates. It isn't certain to terminate, but it terminates in some finite time with probability 1. I *think* that's right. In any case, this stopped being about C some time ago. -- Keith Thompson (The_Other_Keith) k@mib.org <http://www.ghoti.net/~kst> San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst> "We must do something. This is something. Therefore, we must do this." -- Antony Jay and Jonathan Lynn, "Yes Minister"
On 2007-06-06 20:18:36 -0700, CBFalconer <cbfalco@yahoo.com> said:
> Keith Thompson wrote: >> Richard Heathfield <r @see.sig.invalid> writes: >>> Tor Rustad said: > ... snip ... >>>> Arrgh.. exponential-time??! The worst sorting algorithms I know, >>>> are O(N^2). :-/ >>>> I can't remember Knuth or Sedgewick, discussing anything worse >>>> than that. >>>> Give a hint please.. >>> Well, let's see now... >>> while not sorted >>> exchange two elements at random >>> endwhile >>> That would do it, I think. >> If the exchanges are truly random, that's not guaranteed to >> terminate, so it doesn't qualify as an algorithm. > Yes it is, given sufficient time and a really random generator :-)
No, given a truly random number generator, the probability that it will terminate *approaches* 100% as time approaches infinity. However you never have an absolute guarantee that it will terminate as there is a non-zero chance that , for instance, the sequence of numbers is nothing but the number 42 repeated an infinite number of times. -- Clark S. Cox III clarkc@gmail.com
On 6 Jun, 17:29, "Joachim Schmitz" <nospam.j@schmitz-digital.de> wrote:
> "CBFalconer" <cbfalco @yahoo.com> schrieb im Newsbeitrag news:4666D14E.D9A3A057@yahoo.com... > > mark_blue@pobox.com wrote: > >> Richard Heathfield <r@see.sig.invalid> wrote: > >>> mark_blue@pobox.com said: > >>>> On 6 Jun, 10:50, bele_harshad2@yahoo.co.in wrote: > >>>>> how can i pick up largest no from 5 rows by 5 column matrix???? > >>>> Step 1. Sort the columns of each row into ascending order. > >>>> Step 2. Sort the rows into ascending order using the last column as > >>>> the key. > >>>> Step 3. Pick the last column of the last row. > >>> I'm sure we can do better than O(c log c + r log r). Perhaps we > >>> should specify a particular sort. That can get us right up to > >>> O(c^2 + r^2) without any major effort. But can anyone find an > >>> exponential-time algorithm? > >> There's a big problem here, though - how can we sort anything when > >> we don't know how to tell whether one thing is larger than another? > > You apparantly totally missed the humor involved in RH's post.
I didn't. > Me too I must admit. Isn't that what smileys have been invented for?
As Denis points out, that would ruin the joke. "Dry" humour and irony (both rather British) should never be sullied with emoticons.
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