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Message:

hahahah

Posted by Chin Loong on October 26, 2001 at 4:57 AM

> Now if you can post a really interesting homework assignment that will teach me something new as I write it, then maybe I'll write it (but you'll have to also tell me the due date, so I can post it the day after). Which reminds me, Chin, I came up with a pretty cool variation of that "draw the diamond" homework from a while back. I'll post it some time later (here's a teaser: it takes a command-line parameter specifying which grade you'd like on the project and uses a different algorithm for each grade from F to A+ (yes, I had too much time on my hands)).

> - Chet

hey! that's cool! :p u can pass the codes here so that we can play around with it ;) i'm a bit busy with new incoming "potential" application projects rite now but i sure can find time to have some fun ^_^

Chet, remember a while back somebody asked for the algorithm of a odd-numbered n x n matrix squares which has the numbers of 1 to (n x n) inside each square which all sums up to the same total (horizontally, vertically, and if i'm not mistaken, diagonally too). well, when i was young i really loved to play with that algorithm, and i was seriously tempted to post the answer.. but well, guilt held me back :p. he gotta do his own assignment ;)

anyway, that's a pretty interesting algorithm.. i didn't exactly tried (i was still pretty young at that time) to figure out the formula/algorithm.. but it follows certain rules.

#assuming left-bottom most square is (0,0) and coord <=> (i,j)

1. i don't know why but i always start with the top row of the matrix, in the middle. place "1" there. ((int)(i_max/2)+1),j_max)

2. head north-east. (i+1,j+1)

for(int NUMBER=2;NUMBER<=nxn;NUMBER++)
{
IF it's a valid square (inside the matrix and empty)
{
place the NUMBER there.
}
ELSE (it's not a valid square)
{
IF it's outside the matrix
{
IF the destination column (i+1) is valid (inside matrix)
{
place the NUMBER at the bottom of the column (i+1,j_min)
}
ELSE IF the destination row (j+1) is valid (inside matrix)
{
place the next number at the left end of the row (i_min,j+1)
}
ELSE IF both the column and row not valid - outside matrix)
{
go down one square (i,j-1) and place the NUMBER there
}
}
ELSE (if not invalid square, must be non-empty square)
{
go down one square (i,j-1) and place the NUMBER there
}
}
}

• argh ~~ Chin Loong October 26, 2001 at 5:02 AM (8)
  • Argh ~~ Matt Gerrans October 26, 2001 at 3:51 PM (0)
  • boxes galore ~ Chin Loong October 26, 2001 at 5:08 AM (6)
    • Impressive! Hiran October 27, 2001 at 11:24 PM (5)
      • i got it all wrong : ( Chin Loong October 28, 2001 at 1:47 AM (2)
        • something wrong with the output Chin Loong October 28, 2001 at 1:51 AM (1)
          • Send me the code plse Hiran October 28, 2001 at 3:27 PM (0)
      • bingo ~ Chin Loong October 28, 2001 at 1:10 AM (0)
      • da Q Chin Loong October 28, 2001 at 1:00 AM (0)