تالار گفتمان nCIS.ir

<?php

//==============================
//fastMapTree.php
function fastMapTree($dataset) {
$tree = array();
foreach ($dataset as $id=>&$node) {
if ($node['parent_id'] === null) {
$tree[$id] = &$node;
} else {
if (!isset($dataset[$node['parent_id']]['child'])) $dataset[$node['parent_id']]['child'] = array();
$dataset[$node['parent_id']]['child'][$id] = &$node;
}
}

return $tree;
}


//=======================================================
//slowMapTree.php
function slowMapTree($dataset, $parent=null, $levels=0) {
if ($levels > 100) {
print ('Possible infinite recursion');
return;
}

$tree = array();
foreach ($dataset as $id=>$node) {
if ($node['parent_id'] !== $parent) continue;
$node['child'] = slowMapTree($dataset, $id, $levels+1);
$tree[$id] = $node;
}

return $tree;
}



//========================
// Build a random dataset
$maxNodes = 1000;
$dataset = array();
for ($i=0;$i<$maxNodes;$i++) {
$parent = rand(-1,$i-1); // We use $i rather than maxNodes here to avoid infinite loops
if ($parent == -1) $parent = null;
$dataset[$i] = array(
'name'=>'Node '.$i,
'parent_id'=>$parent
);
}



//========================
// Initialize variables
$startTime = 0;
$endTime = 0;
$tree = array();

// Build tree
$startTime = microtime(true);
$tree = slowMapTree($dataset);
$endTime = microtime(true);

// Print benchmark
print '<h2>Benchmark slowMapTree</h2>';
print ($endTime-$startTime).' seconds<br>';



//========================
// Initialize variables
$startTime = 0;
$endTime = 0;
$tree = array();

// Build tree
$startTime = microtime(true);
$tree = fastMapTree($dataset);
$endTime = microtime(true);

// Print benchmark
print '<h2>Benchmark fastMapTree</h2>';
print ($endTime-$startTime).' seconds<br>';