Example of how to implement clockwise printing matrix (spiral matrix) in PHP

This article mainly introduces the method of PHP to realize clockwise printing matrix (spiral matrix), involving the related operation skills of PHP based on array traversal, operation simulation printing to realize the spiral matrix function, interested in PHP Friends can refer to this article.

The example in this article describes the method of printing a matrix clockwise in PHP. Share it with everyone for your reference. The details are as follows:

Question

Enter a matrix and print it in clockwise order from outside to inside. Out each number, for example, if you enter the following matrix:

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

will print out the numbers 1,2,3,4,8,12,16,15,14,13,9,5,6,7,11 in sequence ,10.

The solution

is to print in circles, as long as the loop is controlled well.
Pay attention to the situation of single row and single column.

Implementation code

<?php
function printMatrix($matrix)
{
 $row = count($matrix);
 $col = count($matrix[0]);
 if($row == 0 || $col == 0)
  return $matrix;
 $result = array();
 $left = 0;$right = $col-1; $top = 0;$bottom = $row-1;
 while($left<=$right && $top<= $bottom){
  for($i =$left;$i<=$right;++$i){
   array_push($result, $matrix[$top][$i]);
  }
  for($i =$top+1;$i<=$bottom;++$i)
   array_push($result, $matrix[$i][$right]);
  if($top!=$bottom){
   for($i = $right-1;$i>=$left;--$i)
    array_push($result, $matrix[$bottom][$i]);
  }
  if($left!=$right){
   for($i = $bottom-1;$i>$top;--$i)
    array_push($result, $matrix[$i][$left]);
  }
  $left++;$right--;$top++;$bottom--;
 }
 return $result;
}

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