Using forloop to populate brackets

问题

I want to learn to use for loop to populate brackets such as the following:- $max starts at 8 and can be maximum of 512. I only know very basics of forloop, not too well to form the below brackets.. can someone help me on this and explain how they done it. Each goes into simple pattern/sequence.

I appreciate it very much.

$max = 8;

if($max == 8)

[[0, 0], [0, 0]],   
[[0, 0], [0, 0]], 
[[0, 0]],
[[0, 0]]

if($max == 16)

[[0,0], [0,0], [0,0], [0,0]],
[[0,0], [0,0], [0,0], [0,0]],
[[0,0], [0,0]],
[[0,0], [0,0]],
[[0,0]],
[[0,0]]

if($max == 32)

[[0,0], [0,0], [0,0], [0,0], [0,0], [0,0], [0,0], [0,0]],
[[0,0], [0,0], [0,0], [0,0], [0,0], [0,0], [0,0], [0,0]],
[[0,0], [0,0], [0,0], [0,0]],
[[0,0], [0,0], [0,0], [0,0]],
[[0,0], [0,0]],
[[0,0], [0,0]],
[[0,0]],
[[0,0]]

etc until 512. Thanks

回答1:

So basically this would do:

$max = 8;
$arrays = array();
for($i = $max/4; $i >= 1; $i/=2) {
  $array = array_fill(0, $i, array(0,0));
  $arrays[] = $array;
  $arrays[] = $array;
}

And as a string:

$max = 8;
$arrays = array();
for($i = $max/4; $i >= 1; $i/=2) {
  $array = array_fill(0, $i, '[0,0]');
  $array = '['.implode(', ', $array).']';
  $arrays[] = $array;
  $arrays[] = $array;
}
$arrays = implode(",\n", $arrays);

来源：https://stackoverflow.com/questions/18449679/using-forloop-to-populate-brackets