Programa Php para imprimir una array dada en forma de espiral inversa

PHP

<?php
// PHP Code for Print a given 
// matrix in reverse spiral form
$R=3;
$C=6;
 
// Function that print matrix
// in reverse spiral form.
function ReversespiralPrint($m, $n, array $a)
{
     
    // Large array to initialize it
    // with elements of matrix
    $b;
     
    // k - starting row index
    // l - starting column index
    $k = 0;
    $l = 0;
     
    // Counter for single dimension array
    // in which elements will be stored
    $z = 0;
     
    // Total elements in matrix
    $size = $m*$n;
 
    while ($k < $m && $l < $n)
    {
         
        // Variable to store
        // value of matrix.
        $val;
         
        // Print the first row from
        // the remaining rows
        for ($i = $l; $i < $n; ++$i)
        {
            $val = $a[$k][$i];
            $b[$z] = $val;
            ++$z;
        }
        $k++;
 
        // Print the last column from
        // the remaining columns
        for ($i = $k; $i < $m; ++$i)
        {
             
            // printf("%d ", a[i][n-1]);
            $val = $a[$i][$n-1];
            $b[$z] = $val;
            ++$z;
        }
        $n--;
 
        // Print the last row from
        // the remaining rows
        if ( $k < $m)
        {
            for ($i = $n-1; $i >= $l; --$i)
            {
                 
                // printf("%d ", a[m-1][i]);
                $val = $a[$m-1][$i];
                $b[$z] = $val;
                ++$z;
            }
            $m--;
        }
 
        // Print the first column
        // from the remaining columns
        if ($l < $n)
        {
            for ($i = $m - 1; $i >= $k; --$i)
            {
                $val = $a[$i][$l];
                $b[$z] = $val;
                ++$z;
            }
            $l++;
        }
    }
    for ($i = $size - 1; $i >= 0; --$i)
    {
        echo $b[$i]." ";
    }
}
 
    // Driver Code
    $a= array(array(1, 2, 3, 4, 5, 6),
              array(7, 8, 9, 10, 11, 12),
              array(13, 14, 15, 16, 17, 18));
    ReversespiralPrint($R, $C, $a);
 
// This Code is contributed by mits
?>