Examples of php generating all two-digit (numbers, letters) combinations from 0-9, a-z

This article introduces an example of using PHP to generate all two-digit combinations from 0-9, a-z. Friends in need can refer to it.

This section introduces a piece of php code to output any two-digit number composed of numbers and letters.

Thinking Analysis: If the limit is two digits, consider whether the first digit is required to be not 0. If the first digit is allowed to be zero, it will be 36 * 36, that is, a complete arrangement. There are 36 situations in the first place, and there are also 36 situations in the second place. The answer is: The 36 cases in the first place multiplied by the 36 cases in the second place => 36 * 36.

If the first digit is not allowed to be zero, the first digit is 35 cases, and the answer is 35 * 36.

Three to four digits and so on, 36 * 36 * 36 (the first three digits can be zero).

The code is as follows:

<?php
/**
* 生成0-9,a-z任意的二位数组合
* edit by bbs.it-home.org
*/
function all(){
 $jichu = array(0,1,2,3,4,5,6,7,8,9,'a','b','c','d','e','f','g','h','i','j',
'k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z');
 $c = count($jichu );
 for($i=1;$i<=36;$i++){
     $j = $i-1;
     foreach($jichu as $k){
  echo $k.$jichu[$j].'<br />';
     }
 }
}
all();
?>