Help with do while statement.

[fewkesy]

Trying to code a first fit algorithm (explanation here). It doesn't output everything correctly at the end. There probably is an easier way to achieve this, but I need to do it using do and while statements.

 

From the output I only get the first array, none of the others display.

 

function first_fit(&$arr, &$max)
{
$bin = array(array(), array(), array(), array(), array(), array(), array(), array(), array() ,array() );
$i=0;
$j=0;	
do
{
do
{
	if (array_sum($bin[$j])+$arr[$i] <= $max) {$bin[$j][] = $arr[$i]; $k=1;	}
	$j++;
}
while($k = 0);
$i++;
$j=0;
}
while($i<=9);
outputarray($bin[0]);
outputarray($bin[1]);
outputarray($bin[2]);
outputarray($bin[3]);
outputarray($bin[4]);
outputarray($bin[5]);
outputarray($bin[6]);
outputarray($bin[7]);
outputarray($bin[8]);
outputarray($bin[9]);
}

 

 

The function outputarray() just prints the array in a nicely formatted way.

 

Any help would be much appreciated.

[btherl]

Where do you reset $k back to 0?

 

On a side note, you should remove the "&" in front of $arr and $max at the top of your code, unless you really do need to alter the value of those variables outside the function.

[fewkesy]

Thanks for the response.

 

I'd forgot to reset $k, so I put it after the $j reset, however it still did not solve the problem.

 

I am aware of the ampersands and they have been put there on purpose due to other parts of the script.

 

Any more ideas?

 

If it helps $arr is an array of 10 numeric values, and $max is a single numeric value.

[btherl]

I would add some debugging statements.  Each time you add to a bin, print out "Adding block of size {$arr[$i]} to bin $j\n".  And also print out each time you consider a bin and a block.  Printing out the values of $i, $j and $k at each step woudl be good too.

[btherl]

I was also a bit confused as to why this wasn't working so I looked into it further.. it turns out the problem is in this line:

 

while ($k = 0);

 

I'll leave it to you to work out what is wrong with it and why it makes the script act that way

[fewkesy]

Thanks, can't believe it was that simple.

 

Just in case anyone does wonder solved by changing the line to

while ($k == 0;)