PHP implements clockwise print matrix (spiral matrix) method example, matrix example
This example describes how PHP implements a clockwise print matrix. We will share this with you for your reference. The details are as follows:
Problem
Enter a matrix and print each number in clockwise order from the external, for example, if you enter the following matrix:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
The numbers 1, 2, 3, 4, 8, 12, 16, 15, 14, 13, 9, 5, 6, 7, 11, 10 are printed in sequence.
Solution
It is printed in a circle, as long as the loop is well controlled.
Pay attention to the single row and single column.
Implementation Code
<?phpfunction 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;}