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PHP heap sort (heapsort) exercise_PHP tutorial

Jul 13, 2016 am 10:25 AM
php Heap sort

Copy code The code is as follows:

//Heap sort application
class heapsort
{
var $a;
function setarray($a)//Get array
{
$this->a=$a;
}
function runvalue($b,$c)//$a represents the array, $b represents the sorted heap, $c represents the end point,
{
while($b<$c)
{
$h1=2*$b;
$h2=(2*$b+1);
if($h 1> ;$c)
break;
elseif($h1==$c)
{
if($this->a[$b]>$this->a[$ h1])
                                                                                                     . 🎜>             $this->a[$h1]=$t;
                                                                                                                           🎜>              $la=1;
                                                                                                                                                                                    $this->a[$b]>$this->a[$h1])||($this->a[$b]>$this->a[$h2]))
                                                                                                                                            $t=$this->a[ $h2];
                                                                                                             $ b=$h2;
}
else
🎜>                       $this->a[$h1]=$this ->a[$b];
$this->a[$b]=$t;
$b=$h1;
}
      }
                                                                              else $la=1;
if($la==1)
break;
}
}
    function getarray()
      {
        $all=count($this->a);
        $b=Floor(($all-1)/2);
        for($i=$b;$i>=1;$i--)//先将数组建立成堆
          {
            $this->runvalue($i,($all-1));
          }
        for($i=1;$i<$all;$i++)
          {
            $a1=($all-$i);
            if($i==1)
              {
                $t=$this->a[1];
                $this->a[1]=$this->a[$a1];
                $this->a[$a1]=$t;
              }
            else
              {
                $end=($all-$i);
                $this->runvalue(1,$end);
                $t=$this->a[1];
                $this->a[1]=$this->a[$end];
                $this->a[$end]=$t;
              }
          }
        return $this->a;
      }
  }
//////
class sortarr
  {
    var $a;
    function setarray($a)//取得数组
      {
        $this->a=$a;
      }
    function runvalue($i)
      {
        $max=$this->a[$i];
        $id=$i;
        for($j=($i+1);$ja);$j++)
          {
            if($this->a[$j]>$max)
              {
                $max=$this->a[$j];
                $id=$j;
              }
          }
        if($id!=$i)
          {
            $t=$this->a[$id];
            $this->a[$id]=$this->a[$i];
            $this->a[$i]=$t;
          }
      }
    function getarray()
      {
        for($i=1;$i<(count($this->a)-1);$i++)
          $this->runvalue($i);
        return $this->a;
      }
  }
//////
$s=microtime();
$st=explode(' ',$s);
$st1=$st[0];
$st2=$st[1];
//////
$v=10000;//排序数组长度
$brr[0]=0;
for($i=1;$i<$v;$i++)
  {
    $brr[$i]=rand();
  }
$check=2;//1 stand for heapsort 2 stand for another sort
echo'after sort!!
';
if($check==1)
  {
    $arr=new heapsort;
    $arr->setarray($brr);
    $ok=$arr->getarray();
    for($i=1;$i<$v;$i++)
      {
        $j=((($i+1)>($v-1))?($v-1):($i+1));
  /*
 if($ok[$j]<$ok[$i])
          echo''.$ok[$i].'
';
        else
          echo$ok[$i].'
';*/
      }
  }
elseif($check==2)
  {
    $arr=new sortarr;
    $arr->setarray($brr);
    $ok=$arr->getarray();
    for($i=1;$i<$v;$i++)
      {
        $j=((($i+1)>($v-1))?($v-1):($i+1));/*
        if($ok[$j]<$ok[$i])
          echo''.$ok[$i].'
';
        elseif($ok[$j]>$ok[$i])
          echo''.$ok[$i].'
';
        else
          echo$ok[$i].'
';*/
      }
  }
elseif($check==3)
  {
    sort($brr);
    $ok=$brr;
    for($i=1;$i<$v;$i++)
      {
        $j=((($i+1)>($v-1))?($v-1):($i+1));/*
        if($ok[$j]<$ok[$i])
          echo''.$ok[$i].'
';
        elseif($ok[$j]>$ok[$i])
          echo''.$ok[$i].'
';
        else
          echo$ok[$i].'
';*/
      }
  }
else
  {
    echo'参数输入错误!!
';
  }
//////
$s=microtime();
$st=explode(' ',$s);
$sta=$st[0];
$stb=$st[1];
$ss1=$sta-$st1;
$ss2=$stb-$st2;
if($check==1)
  $word='堆排序';
elseif($check==2)
  $word='常规排序';
elseif($check==3)
  $word='普通排序';
else
  $word='无排序';
echo$word.'对具有'.$v.'个元素的数组排序,消耗了'.($ss2+$ss1).'秒时间';
//////
?>

www.bkjia.comtruehttp://www.bkjia.com/PHPjc/825187.htmlTechArticle复制代码 代码如下: ? //堆排序应用 class heapsort { var $a; function setarray($a)//取得数组 { $this-a=$a; } function runvalue($b,$c)//$a 代表数组,$b代表排序...
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