Home php教程 php手册 PHP 冒泡排序 二分查找 顺序查找 二维数组排序算法函数的详解

PHP 冒泡排序 二分查找 顺序查找 二维数组排序算法函数的详解

Jun 13, 2016 am 11:45 AM
php use bubble function sort data structure array document Find of program algorithm Detailed explanation important order

数据结构很重要,算法+数据结构+文档=程序
使用PHP描述冒泡排序算法,对象可以是一个数组

复制代码 代码如下:


//冒泡排序(数组排序)
function bubble_sort($array) {
$count = count($array);
if ($count return false;
for($i=0; $ifor($j=$count-1; $j>$i; $j–){
if ($array[$j] $tmp = $array[$j];
$array[$j] = $array[$j-1];
$array[$j-1] = $tmp;
}
}
}
return $array; }


使用PHP描述顺序查找和二分查找(也叫做折半查找)算法,顺序查找必须考虑效率,对象可以是一个有序数组

复制代码 代码如下:


//二分查找(数组里查找某个元素)
function bin_sch($array, $low, $high, $k){
if ($low $mid = intval(($low+$high)/2);
if ($array[$mid] == $k){
return $mid;
}elseif ($k return bin_sch($array, $low, $mid-1, $k);
}else{
return bin_sch($array, $mid+1, $high, $k);
}
}
return -1;
}
//顺序查找(数组里查找某个元素)
function seq_sch($array, $n, $k){
$array[$n] = $k;
for($i=0; $iif($array[$i]==$k){
break;
}
}
if ($ireturn $i;
}else{
return -1;
}
}


写一个二维数组排序算法函数,能够具有通用性,可以调用php内置函数

复制代码 代码如下:


//二维数组排序, $arr是数据,$keys是排序的健值,$order是排序规则,1是升序,0是降序
function array_sort($arr, $keys, $order=0) {
if (!is_array($arr)) {
return false;
}
$keysvalue = array();
foreach($arr as $key => $val) {
$keysvalue[$key] = $val[$keys];
}
if($order == 0){
asort($keysvalue);
}else {
arsort($keysvalue);
}
reset($keysvalue);
foreach($keysvalue as $key => $vals) {
$keysort[$key] = $key;
}
$new_array = array();
foreach($keysort as $key => $val) {
$new_array[$key] = $arr[$val];
}
return $new_array;
}


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