我需要编写一个函数，通过字母表其中迭代（AZ）所示： （下面是一个例子了-C）

I need to write a function which iterates through alphabet (a-z) like this: (here is an example for a-c)

a
b
c

aa
ab
ac

ba
bb
bc

ca
cb
cc

aaa
aab
aac

... and so on. (until the word has 5 characters)

任何想法如何做到这一点？我想我需要一些递归函数。

any idea how to do this? I guess I need some recursive function.

推荐答案

无需递归！

for($char = 'a'; $char != 'aaaaaa'; $char++){
    echo $char . PHP_EOL;
}