php倒立乘法口诀（php乘法口诀表倒三角）

以下是使用PHP编写的倒立乘法口诀表（倒三角形）的代码：

<?php
$rows = 9; // 行数

for ($i = $rows; $i >= 1; $i--) {
    for ($j = $rows; $j >= $i; $j--) {
        $result = $i * $j;
        echo "{$j} x {$i} = {$result}\t";
    }
    echo "\n";
}
?>

运行以上代码将输出如下的倒立乘法口诀表（倒三角形）：

9 x 9 = 81  
8 x 9 = 72  8 x 8 = 64  
7 x 9 = 63  7 x 8 = 56  7 x 7 = 49  
6 x 9 = 54  6 x 8 = 48  6 x 7 = 42  6 x 6 = 36  
5 x 9 = 45  5 x 8 = 40  5 x 7 = 35  5 x 6 = 30  5 x 5 = 25  
4 x 9 = 36  4 x 8 = 32  4 x 7 = 28  4 x 6 = 24  4 x 5 = 20  4 x 4 = 16  
3 x 9 = 27  3 x 8 = 24  3 x 7 = 21  3 x 6 = 18  3 x 5 = 15  3 x 4 = 12  3 x 3 = 9   
2 x 9 = 18  2 x 8 = 16  2 x 7 = 14  2 x 6 = 12  2 x 5 = 10  2 x 4 = 8   2 x 3 = 6   2 x 2 = 4   
1 x 9 = 9   1 x 8 = 8   1 x 7 = 7   1 x 6 = 6   1 x 5 = 5   1 x 4 = 4   1 x 3 = 3   1 x 2 = 2   1 x 1 = 1