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HomeBackend DevelopmentPHP Tutorial刚刚遇到一个棘手的算法问题,求解


求解


回复讨论(解决方案)

$a = array(1,2,2,3,1,2,3,1,1);$st = array(1 => 0);$d = 1;foreach($a as $v) {  @$st[$v]++;  if($v >= $d) {    $d = $v;  }else{    while($v < $d) {      unset($st[$d--]);    }  }  $r[] = join('.', $st);}print_r($r); 
Array
(
    [0] => 1
    [1] => 1.1
    [2] => 1.2
    [3] => 1.2.1
    [4] => 2
    [5] => 2.1
    [6] => 2.1.1
    [7] => 3
    [8] => 4
)

不好意思,没看明白是个啥意思。……。。…。…………。……。。…。……。。…。……。……。………

$a = array(1,2,2,3,1,2,3,1,1);$st = array(1 => 0);$d = 1;foreach($a as $v) {  @$st[$v]++;  if($v >= $d) {    $d = $v;  }else{    while($v < $d) {      unset($st[$d--]);    }  }  $r[] = join('.', $st);}print_r($r); 
Array
(
    [0] => 1
    [1] => 1.1
    [2] => 1.2
    [3] => 1.2.1
    [4] => 2
    [5] => 2.1
    [6] => 2.1.1
    [7] => 3
    [8] => 4
)


版主,谢谢你的解答 ,如果可以的话,能不能讲讲你的思路呀,万分感谢

不好意思,没看明白是个啥意思。……。。…。…………。……。。…。……。。…。……。……。………


本题其实是一个目录编排的问题,你可以看到优先级决定着大小标题的显示

$a = array(1,2,2,3,1,2,3,1,1); 表示的是节点所在的层次
$st = array(1 => 0); 存储每层当前的序号
$d 表示当前的层次

嗯嗯 谢谢版主的解释,我再好好研究研究,先把分送上

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