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

jacklove
jackloveOriginal
2018-07-02 17:57:441874browse

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

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:


##12 34##5913 will print out the numbers 1,2,3,4,8,12,16,15,14,13, 9,5,6,7,11,10.
6 7 8
10 11 12
14 15 16

The solution is to print in circles, as long as the loop is controlled well can.

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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