A question I met today.

Today, a face test, ask for high-finger teaching
The title requirement is to write a function, enter a number n, and then the function will output an n-row n-column array, the array pattern is as follows:

N=3
-------------------
1 2 3
8 9 4
7 6 5

N=4
-------------------
1 2 3 4
12 13 14 5
11 16 15 6
10 9 8 7

N=5
-------------------
1 2 3) 4 5
16 17 18) 19 6
15 24 25) 20 7
14 23 22) 21 8
13 12 11) 10 9

Well, that's roughly the way it is, sort of around the circle.


→→→→┐
┌→→┐↓
↑┌→↓↓
↑└←┘↓
└←←←┘

-------------------
Have the wood has the master to make? 0.0

------Solution--------------------

PHP Code

function Circle ($n) {$k = $n% 2;  $ar = Array ();  for ($i =0; $i < $n; $i + +) $ar [$i] = Array_fill (0, $n, 0);  $p = 1;  $x = 0;  $y = 0;  $m = 0;  $len = $n * $n;    while ($p < $len) {$x = $y = $m;    while ($x < $n) $ar [$y] [$x + +] = $p + +;    $x--;    $y + +;    while ($y < $n) $ar [$y ++][$x] = $p + +;    $y--;    $x--;    while ($x >= $m) $ar [$y] [$x-] = $p + +;    $x + +;    $y--;    $m + +;    while ($y >= $m) $ar [$y--][$x] = $p + +;  $n--;  if ($k) $ar [$y +1][$x +1] = $p;  $r = ' 
   
     '; foreach ($ar as $v) $r. = ' 
    ';  return $r. ' 
    
 
     
 
      
 '. Join (' 
 
      
 ', $v).  '
   
     
 
   
 ';      }for ($i =2; $i <30; $i + +) {$html. = Circle ($i);  $html. = ';      }?> !--? php echo $html?--> 
 