致命錯誤：允許內存大小爲25165824字節耗盡（試圖分配35個字節）

我在PHP中使用Dijkstra算法。但我得到這個錯誤致命錯誤：允許內存大小爲25165824字節耗盡（試圖分配35個字節）

Fatal error: Allowed memory size of 25165824 bytes exhausted (tried to allocate 35 bytes) in C:\AppServ\www\direction\dijkstra.php on line 100

如何優化算法，以減少內存消耗

<?php 
ini_set('memory_limit', '1M'); //Raise to 512 MB 
ini_set('max_execution_time', '60'); //Raise to 512 MB 
class Dijkstra { 

    var $visited = array(); 
    var $distance = array(); 
    var $previousNode = array(); 
    var $startnode =null; 
    var $map = array(); 
    var $infiniteDistance = 0; 
    var $numberOfNodes = 0; 
    var $bestPath = 0; 
    var $matrixWidth = 0; 

    function Dijkstra(&$ourMap, $infiniteDistance) { 
     $this -> infiniteDistance = $infiniteDistance; 
     $this -> map = &$ourMap; 
     $this -> numberOfNodes = count($ourMap); 
     $this -> bestPath = 0; 
    } 

    function findShortestPath($start,$to) { 
     $this -> startnode = $start; 
     for ($i=0;$i<$this -> numberOfNodes;$i++) { 
      if ($i == $this -> startnode) { 
       $this -> visited[$i] = true; 
       $this -> distance[$i] = 0; 
      } else { 
       $this -> visited[$i] = false; 
       $this -> distance[$i] = isset($this -> map[$this -> startnode][$i]) 
        ? $this -> map[$this -> startnode][$i] 
        : $this -> infiniteDistance; 
      } 
      $this -> previousNode[$i] = $this -> startnode; 
     } 

     $maxTries = $this -> numberOfNodes; 
     $tries = 0; 
     while (in_array(false,$this -> visited,true) && $tries <= $maxTries) {    
      $this -> bestPath = $this->findBestPath($this->distance,array_keys($this -> visited,false,true)); 
      if($to !== null && $this -> bestPath === $to) { 
       break; 
      } 
      $this -> updateDistanceAndPrevious($this -> bestPath);    
      $this -> visited[$this -> bestPath] = true; 
      $tries++; 
     } 
    } 

    function findBestPath($ourDistance, $ourNodesLeft) { 
     $bestPath = $this -> infiniteDistance; 
     $bestNode = 0; 
     for ($i = 0,$m=count($ourNodesLeft); $i < $m; $i++) { 
      if($ourDistance[$ourNodesLeft[$i]] < $bestPath) { 
       $bestPath = $ourDistance[$ourNodesLeft[$i]]; 
       $bestNode = $ourNodesLeft[$i]; 
      } 
     } 
     return $bestNode; 
    } 

    function updateDistanceAndPrevious($obp) {   
     for ($i=0;$i<$this -> numberOfNodes;$i++) { 
      if( (isset($this->map[$obp][$i])) 
       && (!($this->map[$obp][$i] == $this->infiniteDistance) || ($this->map[$obp][$i] == 0))  
       && (($this->distance[$obp] + $this->map[$obp][$i]) < $this -> distance[$i]) 
      )  
      { 
        $this -> distance[$i] = $this -> distance[$obp] + $this -> map[$obp][$i]; 
        $this -> previousNode[$i] = $obp; 
      } 
     } 
    } 

    function printMap(&$map) { 
     $placeholder = ' %' . strlen($this -> infiniteDistance) .'d'; 
     $foo = ''; 
     for($i=0,$im=count($map);$i<$im;$i++) { 
      for ($k=0,$m=$im;$k<$m;$k++) { 
       $foo.= sprintf($placeholder, isset($map[$i][$k]) ? $map[$i][$k] : $this -> infiniteDistance); 
      } 
      $foo.= "\n"; 
     } 
     return $foo; 
    } 

    function getResults($to) { 
    if(trim($to)!="") 
    { 
     $ourShortestPath = array(); 
     $foo = ''; 
     for ($i = 0; $i < $this -> numberOfNodes; $i++) { 
      if($to !== null && $to !== $i) { 
       continue; 
      } 
      $ourShortestPath[$i] = array(); 
      $endNode = null; 
      $currNode = $i; 
      $ourShortestPath[$i][] = $i; 
      while ($endNode === null || $endNode != $this -> startnode) { 
       $ourShortestPath[$i][] = $this -> previousNode[$currNode]; 
       $endNode = $this -> previousNode[$currNode]; 
       $currNode = $this -> previousNode[$currNode]; 
      } 
      $ourShortestPath[$i] = array_reverse($ourShortestPath[$i]); 
      if ($to === null || $to === $i) { 
      if($this -> distance[$i] >= $this -> infiniteDistance) { 
       $foo .= sprintf("no route from %d to %d. \n",$this -> startnode,$i); 
      } else { 
       $foo .= sprintf(' - Distance = %d (km) <br> - Walking time ~ %d (hrs)<br> - Running time ~ %d (hrs)<br> - Driving time ~ %d (hrs)<br> Nodes [%d] : %s'."\n" , 
         $this -> distance[$i], round($this -> distance[$i]/5,2),$this -> distance[$i]/17.2,$this -> distance[$i]/50, 
         count($ourShortestPath[$i]), 
         implode('-',$ourShortestPath[$i])); 
      } 
       if ($to === $i) { 
        break; 
       } 
      } 
     } 
     } 
     else $foo=""; 
     return $foo; 
    } 
} // end class 
?>

來源

2011-06-15 Adham

這不是問題。請你重新編輯並解釋你不瞭解的內容。 – 2011-06-15 19:25:21

請顯示一些代碼。 – hakre 2011-06-15 19:28:14

@hakre我編輯了這個問題 – Adham 2011-06-15 19:38:20

它似乎你真的耗盡內存，這正是內存24MB。您可以通過在php.ini中修改memory_limit來修改PHP的最大內存量。

你能展示你的算法嗎？

來源

2011-06-15 19:25:09

該腳本使用了它有權使用的所有內存。嘗試提高php.ini中的內存限制或代碼如下：

ini_set('memory_limit', '512M'); //Raise to 512 MB

來源

2011-06-15 19:28:46 AlexV

致命錯誤：允許內存大小爲25165824字節耗盡（試圖分配35個字節）

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