php - 如何从 php 中的字符串创建可能的字符串组合？

Question

如何从 php 中的字符串创建可能的字符串组合

实验:

input = 'abc';
output = array(
  [0]=> "a"
  [1]=> "ab"
  [2]=> "abc"
  [3]=> "ac"
  [4]=> "acb"
  [5]=> "b"
  [6]=> "ba"
  [7]=> "bac"
  [8]=> "bc"
  [9]=> "bca"
  [10]=> "c"
  [11]=> "ca"
  [12]=> "cab"
  [13]=> "cb"
  [14]=> "cba"
)

求助，谢谢

Answer 1

Fasil kk 的代码可能会遇到“最大函数嵌套级别” fatal error ，

如果你有这个问题，试试这个:

$letters = str_split("abc");

$combos = $letters;
$lastres = $letters;
for ($i = 1; $i < count($letters); $i++) {
    $newres = array();
    foreach ($lastres as $r) {
        foreach ($letters as $let) {
            $newres[] = $r . $let;
        }
    }

    foreach ($newres as $w) {
        $combos[] = $w;
    }

    $lastres = $newres;
}

print_r($combos);

那么你只需要担心内存:)