我有一个代码可以为锦标赛生成括号表。我有球员,每个球员都与一所学校相关联。我需要对一个包含球员的数组进行排序,这样就不会有同一学校球员的第一场比赛(或者可能是较低的同校比赛)。
像这样:
$players = array(
array('name' => 'juan', 'school' => 'ABC'), // 0
array('name' => 'leo', 'school' => 'ABC'), // 1
array('name' => 'arnold', 'school' => 'DEF'), // 2
array('name' => 'simon', 'school' => 'DEF'), // 3
array('name' => 'luke', 'school' => 'ECD'), // 4
array('name' => 'ash', 'school' => 'ECD'), // 5
);
// code to sort here
array_chunk($players, 2); // this generate an array with groups of two for matches.
在上面的例子中,[0] 和 [1] 不能在一起,因为他们在同一所学校。例如,[0] 可以与 3 一起使用。
我正在尝试使用 usort,但我不确定处理此问题的正确方法是什么。
最佳答案
好的,重新检查问题后的新答案。我认为该算法应该是这样的:
- 遍历未分配的玩家(注意此列表一次减少 2 个)。
- 找到剩余可用玩家最多的学校,该学校不是当前玩家迭代所在的学校。
- 如果上述检查没有找到有任何玩家的学校,则求助于使用当前迭代玩家所在的同一所学校。这具有这样的效果,如果没有其他玩家留在同一学校,则同一学校的玩家可以互相玩分配池。
- 从我们刚刚找到的学校分配一个任意玩家
- 配对当前迭代的播放器和任意播放器
- 将两名玩家从池中移除
在实现方面,我发现维护 2 个索引更容易 - 一个学校和 1 个玩家。我将它捆绑到几个类中,因为对象固有的引用性质使生活更轻松。我的代码在下面......它开箱即用,但可能需要一些调整。
<?php
class School {
protected $name;
protected $players = [];
public function __construct($name) {
$this->name = $name;
}
public function get_name() {
return $this->name;
}
public function add_player($name) {
$this->players[] = $name;
}
public function del_player($name) {
if (($index = array_search($name, $this->players)) !== false) {
unset($this->players[$index]);
}
}
public function player_count() {
return count($this->players);
}
public function get_player() {
if (!reset($this->players)) {
return false;
}
return [
'school' => $this->name,
'name' => reset($this->players),
];
}
}
class Players {
protected $schools_index = [];
protected $player_index = [];
public function add_player($school, $player) {
// Create school if not exists
if (!isset($this->schools_index[$school])) {
$this->schools_index[$school] = new School($school);
}
// Add player to school and own index
$this->schools_index[$school]->add_player($player);
$this->player_index[$player] = $school;
}
public function del_player($school, $player) {
// From school index
$this->schools_index[$school]->del_player($player);
// From own index
if (isset($this->player_index[$player])) {
unset($this->player_index[$player]);
}
}
public function biggest_school($exclude = null) {
$rtn = null;
// Find school excluding the exclude. Don't get schools with nobody left in them.
foreach ($this->schools_index as $name=>$school) {
if ((!$exclude || $name != $exclude) && ($school->player_count()) && (!$rtn || $rtn->player_count() < $school->player_count())) {
$rtn = $school;
}
}
// If we didn't get a school, shitcan the exclude and try the excluded school
if (!$rtn && $exclude) {
if ($this->schools_index[$exclude]->player_count()) {
$rtn = $this->schools_index[$exclude];
}
}
return $rtn;
}
public function get_player() {
if (!reset($this->player_index)) {
return false;
}
return [
'school' => reset($this->player_index),
'name' => key($this->player_index),
];
}
public static function from_players_arr(array $players) {
$obj = new static();
foreach ($players as $player) {
// Add to indexes
$obj->add_player($player['school'], $player['name']);
}
return $obj;
}
}
$players = array(
array('name' => 'juan', 'school' => 'ABC'),
array('name' => 'leo', 'school' => 'ABC'),
array('name' => 'arnold', 'school' => 'ABC'),
array('name' => 'simon', 'school' => 'ABC'),
array('name' => 'luke', 'school' => 'ABC'),
array('name' => 'alan', 'school' => 'JKL'),
array('name' => 'jeff', 'school' => 'BAR'),
array('name' => 'paul', 'school' => 'FOO'),
);
$players_obj = Players::from_players_arr($players);
$pairs = [];
while ($player = $players_obj->get_player()) {
$players_obj->del_player($player['school'], $player['name']);
$opponent = $players_obj->biggest_school($player['school'])->get_player();
$pairs[] = [
$player['name'],
$opponent['name'],
];
$players_obj->del_player($opponent['school'], $opponent['name']);
}
var_dump($pairs);
输出如下:
array(4) {
[0] =>
array(2) {
[0] =>
string(4) "juan"
[1] =>
string(4) "alan"
}
[1] =>
array(2) {
[0] =>
string(3) "leo"
[1] =>
string(4) "jeff"
}
[2] =>
array(2) {
[0] =>
string(6) "arnold"
[1] =>
string(4) "paul"
}
[3] =>
array(2) {
[0] =>
string(5) "simon"
[1] =>
string(4) "luke"
}
}
关于PHP 以两组为一组对数组进行排序,避免合并具有相同值的项目,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19387326/