求这种的算法-PHP Tutorial-php.cn

求这种的算法

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Release： 2016-06-23 14:09:14

Original

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比如我现在有一个数组

$array=Array("a",'b','c','d','e','f','g');

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当然不止这么几个

我想要输出的结果是：

a
b
c
d
e
f
g
aa
ab
ac
ad
ae
af
ag
ba
bb
bc
bd
be
bf
bg
ca
cb
cc

…………

gaaaaaaa
gaaaaaab
gaaaaaac
gaaaaaad
gaaaaaae

…………

就是把这些字符能组成的字符串都罗列出来

回复讨论(解决方案)

LZ的问题好像有点歧义吧，比如a这个字母
a算一个 aa算一个 aaa算一个 aaaaaaaaaaaaaaaaaaaaaaaaaa也是一个
要多少是结束啊？

比如我现在有一个数组

$array=Array("a",'b','c','d','e','f','g');

Copy after login

当然不止这么几个

我想要输出的结果是：

a
b
c
d
e
f
g
aa
ab
ac
ad
ae
af
ag
ba
bb
bc
bd
be
bf
bg
ca
cb
cc

…………

gaaaaaaa
gaaaaaab
gaaaaaac
gaaaaaad
gaaaaaae

…………

就是把这些字符能组成的字符串都罗列出来

没问题的，就是要无限个啊。。。

$array=Array("a",'b','c','d','e','f','g');
for($i=-1;$i foreach($array as $k=>$v){
echo $array[$i].$v."
";
}
}
希望能帮到你~

那您这程序啥时候停止啊....

没问题的，就是要无限个啊。。。

那您这程序啥时候停止啊....

没问题的，就是要无限个啊。。。

拔下电源的时候...

估计是想做对撞机

那您这程序啥时候停止啊....

没问题的，就是要无限个啊。。。

拔下电源的时候...

虽然楼主需求看上去有些无厘头，但如果设定好终止条件也并非不能实现
在有限个数的前提下，这个算法还是很具挑战性的
我先来的抛砖引玉

$ar = array("a",'b','c');print_r(allot($ar, 4));print_r(allot($ar, 2));function allot($ar, $num) {  static $st = array(); //用于缓存中间结果  $res = array(); //用于承载返回结果  if(! $st) {    $t = $ar;  }else {    $t = array();    foreach($ar as $v) {      $t = array_merge($t, array_map(        function($item, $prefix) {  return $prefix . $item; },        $st, array_fill(0, count($st), $v)));    }  }//  foreach($t as $v) echo $v . PHP_EOL; //直接产生输出  $res = $st = $t;  if($num > 1) $res = array_merge($res, allot($ar, $num-1));  else $st = array(); //初始缓存，以便下一次调用  return $res;}

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Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => aa
    [4] => ab
    [5] => ac
    [6] => ba
    [7] => bb
    [8] => bc
    [9] => ca
    [10] => cb
    [11] => cc
    [12] => aaa
    [13] => aab
    [14] => aac
    [15] => aba
    [16] => abb
    [17] => abc
    [18] => aca
    [19] => acb
    [20] => acc
    [21] => baa
    [22] => bab
    [23] => bac
    [24] => bba
    [25] => bbb
    [26] => bbc
    [27] => bca
    [28] => bcb
    [29] => bcc
    [30] => caa
    [31] => cab
    [32] => cac
    [33] => cba
    [34] => cbb
    [35] => cbc
    [36] => cca
    [37] => ccb
    [38] => ccc
    [39] => aaaa
    [40] => aaab
    [41] => aaac
    [42] => aaba
    [43] => aabb
    [44] => aabc
    [45] => aaca
    [46] => aacb
    [47] => aacc
    [48] => abaa
    [49] => abab
    [50] => abac
    [51] => abba
    [52] => abbb
    [53] => abbc
    [54] => abca
    [55] => abcb
    [56] => abcc
    [57] => acaa
    [58] => acab
    [59] => acac
    [60] => acba
    [61] => acbb
    [62] => acbc
    [63] => acca
    [64] => accb
    [65] => accc
    [66] => baaa
    [67] => baab
    [68] => baac
    [69] => baba
    [70] => babb
    [71] => babc
    [72] => baca
    [73] => bacb
    [74] => bacc
    [75] => bbaa
    [76] => bbab
    [77] => bbac
    [78] => bbba
    [79] => bbbb
    [80] => bbbc
    [81] => bbca
    [82] => bbcb
    [83] => bbcc
    [84] => bcaa
    [85] => bcab
    [86] => bcac
    [87] => bcba
    [88] => bcbb
    [89] => bcbc
    [90] => bcca
    [91] => bccb
    [92] => bccc
    [93] => caaa
    [94] => caab
    [95] => caac
    [96] => caba
    [97] => cabb
    [98] => cabc
    [99] => caca
    [100] => cacb
    [101] => cacc
    [102] => cbaa
    [103] => cbab
    [104] => cbac
    [105] => cbba
    [106] => cbbb
    [107] => cbbc
    [108] => cbca
    [109] => cbcb
    [110] => cbcc
    [111] => ccaa
    [112] => ccab
    [113] => ccac
    [114] => ccba
    [115] => ccbb
    [116] => ccbc
    [117] => ccca
    [118] => cccb
    [119] => cccc
)
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => aa
    [4] => ab
    [5] => ac
    [6] => ba
    [7] => bb
    [8] => bc
    [9] => ca
    [10] => cb
    [11] => cc
)