PHP bubble sort, quick sort, quick search, two-dimensional array deduplication example sharing_PHP tutorial

1. Bubble sort

Copy code The code is as follows:

//Bubble sort
function bubble_sort($array)
{
$count=count($array);
if($count <= 0){
return false;
}
for ($i=0;$i<$count;$i++){
for($j=0;$j<$count-$i-1;$j++){
if( $array[$ j] > $array[$j+1] ){
                                                                                                                array[$j+1]=$temp;
                                                                                                           .
2. Quick sort




Copy code

The code is as follows:

//Quick sort

function quick_sort($array)

{ $count=count($array); if($count <= 1){ return $array; }

$key=$array[0];

$array_left=array();
$array_right=array();
for($i=1;$i<$count;$i++){
if($array[$i] < $key ){
$array_left[]=$array[$i];
}else{
$array_right[]=$array[$i];
}
}
$array_left=quick_sort($array_left);
$array_right=quick_sort($array_right);
return array_merge($array_left,array($key),$array_right);
}

$myarray=array(1,5,3,4,12,10,8);
print_r(bubble_sort($myarray));
echo "
";
print_r(quick_sort($myarray));
echo "
";


3. Quickly find the position where the value first appears

Copy code

The code is as follows:

/**
* Quickly find the position where the value first appears
* @param array $array Array
* @param string $k The value to be found
* @param int $low The smallest key of the search range Value
* @param int $high The maximum key value of the range
*/
function search($array, $k, $low=0, $high=0)
{
// Determine whether it is the first call.
if(count($array)!=0 and $high == 0){
$high = count($array);
}
//If there are remaining array elements
if($low <= $high){
//Take the middle value of $low and $high
$mid = intval(($low+$high)/2);
//If If found, return
if ($array[$mid] == $k){
return $mid;
}
//If not found, continue to search
elseif ($k " k, $mid+1, $high);
}
}
return -1;
}
$array = array(4,5,7,8,9,10, ;
4. Remove duplicate items from the two-dimensional array



Copy the code

The code is as follows:

/** * Remove duplicates in the two-dimensional array * @param $array2D Array * @param $keyArray The key corresponding to the field when restoring 🎜 >*/ public function array_unique_fb($array2D,$keyArray){

$temp=array();

foreach ($array2D as $v){

$v = join(",",$v); //For dimensionality reduction, you can also use implode to convert the one-dimensional array into a string connected with commas

$temp = array_unique($temp); //Remove duplicate strings, that is, repeated one-dimensional arrays
foreach ($temp as $k => $v){
//$ temp[$k] = explode(",",$v); //Reassemble the disassembled array
$temp[$k]= array_combine($keyArray ,explode(",",trim($ v)));
}
return $temp;
}



$testArray=array_unique_fb(array(array('a'=>1,'b'=>2,'c'=>3),
array('a'=>1, 'b'=>2,'c'=>3),array('a'=>1,'b'=>2,'c'=>3)),array('a' ,'b','c''));

print_r($testArray);

http://www.bkjia.com/PHPjc/760290.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/760290.htmlTechArticle1. Bubble sort copy code The code is as follows: //Bubble sort function bubble_sort($array) { $count =count($array); if($count = 0){ return false; } for($i=0;$i$count;$i++){ for($j=0;...