问PHP将人员随机分配给一个团队

EN

<?php

// just preparing the set of players for the demonstration
$numberOfPLayers = 6;
$players = [];
for ($i = 0; $i < $numberOfPLayers; $i++) {
    $players[] = [
        'id' => $i,
        'name' => sprintf("Player %d", $i + 1),
        'team' => null 
    ];
}

// here starts the actual assignment
shuffle($players);

array_walk($players, function(&$player, $index) {
    $player['team'] = $index % 2 ? "Red" : "Blue";
});

usort($players, function($a, $b) {
    return $a['id'] <=> $b['id'];
});

// just a test output of the set of players
print_r($players);

Array
(
    [0] => Array
        (
            [id] => 0
            [name] => Player 1
            [team] => Blue
        )

    [1] => Array
        (
            [id] => 1
            [name] => Player 2
            [team] => Red
        )

    [2] => Array
        (
            [id] => 2
            [name] => Player 3
            [team] => Red
        )

    [3] => Array
        (
            [id] => 3
            [name] => Player 4
            [team] => Blue
        )

    [4] => Array
        (
            [id] => 4
            [name] => Player 5
            [team] => Red
        )

    [5] => Array
        (
            [id] => 5
            [name] => Player 6
            [team] => Blue
        )

)

function createTeams($players) {
  $totalPlayers = count($players);

  if($totalPlayers % 2 == 0) { //even amount of players
    $playersRed = $playersBlue = $totalPlayers / 2;
  } else { //odd amount of players
    $randInt = rand(1,100);
    $playersPerTeam = $totalPlayers / 2;
    if($randInt <= 50) { //team red has an advantage of 1 extra player
      $playersRed = round($playersPerTeam, 0, PHP_ROUND_HALF_UP);
      $playersBlue = round($playersPerTeam, 0, PHP_ROUND_HALF_DOWN);
    } else { //team blue has an advantage of 1 extra player
      $playersRed = round($playersPerTeam, 0, PHP_ROUND_HALF_DOWN);
      $playersBlue = round($playersPerTeam, 0, PHP_ROUND_HALF_UP);
    }
  }

  //This should be random enough for this purpose
  for ($i=0; $i < 4; $i++) {
    shuffle($players);
  }


  //One way to return the teams.
  // $teamRed  = array_slice($players, 0, $playersRed);
  // $teamBlue = array_slice($players, $playersRed, $playersBlue);
  // return array('red' => $teamRed , 'blue' => $teamBlue);

  //Other way to return the createTeams
  for ($i=0; $i < $totalPlayers; $i++) {
    if ($i < $playersRed) { //player is gonna be in team red
      $players[$i]['team'] = 'red';
    } else { //player is gonna be in team blue
      $players[$i]['team'] = 'blue';
    }
  }
  return $players;
}

$players = array ( 0 => array ( 'ID' => '3', 'name' => 'olaf', 'team' => NULL), 1 => array ( 'ID' => '4', 'name' => 'Peter', 'team' => NULL), 2 => array ( 'ID' => '5', 'name' => 'chris', 'team' => NULL), 3 => array ( 'ID' => '6', 'name' => 'günther', 'team' => NULL), 4 => array ( 'ID' => '7', 'name' => 'Max', 'team' => NULL));

for ($i=0; $i < 5; $i++) {
  print_r(createTeams($players));
  echo "<br><br>";
}

$arr = array ( 0 => array ( 'ID' => '3', 'name' => 'olaf', 'team' => NULL, ), 1 => array ( 'ID' => '4', 'name' => 'Peter', 'team' => NULL, ), 2 => array ( 'ID' => '5', 'name' => 'chris', 'team' => NULL, ), 3 => array ( 'ID' => '6', 'name' => 'günther', 'team' => NULL, ), );
// count the number of player in the array and assign to variable
$numOfPlayers = count($arr);

// initiate an empty array to hold the values of the players random unique numbers
$check = array();

  $i = 0; // use a counter to evaluate whether number of players set in array is met
  while($i < count($arr)){ // iterate through foreach loop until we have met the number of players using while loop
    // iterate through each time the while loop fires to get the $value 
    foreach($arr as $key => $value){
      // create a random number between 0 and the number of players present in array 
      // to check and pass into new array if is not set yet
      $random = rand(1,$numOfPlayers);
      // conditional that check if the random number is in the new array, if not we push that as a value into the new array
      // we also check if the persons name is set as a key, if not, we push that as a key into the new aray
      if(!in_array($random, $check) && !array_key_exists($value['name'], $check)){
        // set the new key/value pairs and iterate the counter for the while loop
        $check[$value['name']] = $random;
        $i++;
      }
    }
  }
  // Now see if the two arrays $check and $arr are equal in count
  if(count($check) === count($arr)){
    // now assign teams using modulus
    foreach($arr as $key => $value){ 
      // construct the old array with original values
      $gamers[$key] = $value; 
      // if value is divisible by 2, assign to specific team change operator here 
      // if you want to swap what team get the odd numbered players   
      if($check[$value['name']] % 2 == 0){       
        $gamers[$key]['team'] = 2;
      // else if not divisible by two assign to other team     
      }else{
        $gamers[$key]['team'] = 1;
      }
    }     
  }

function constTeams($arr){
  $numOfPlayers = count($arr);

  $check = array();

  $i = 0;
  while($i < count($arr)){
    foreach($arr as $key => $value){
      $random = rand(1,$numOfPlayers); 
      if(!in_array($random, $check) && !array_key_exists($value['name'], $check)){
        $check[$value['name']] = $random;
        $i++;
      }
    }
  }
  if(count($check) === count($arr)){
    foreach($arr as $key => $value){ 
      $gamers[$key] = $value;     
      if($check[$value['name']] % 2 == 0){        
        $gamers[$key]['team'] = 'Blue';
      }else{
        $gamers[$key]['team'] = 'Red';
      }
    }     
  }
  return $gamers;
}

array(4) {
  [0]=>
  array(3) {
    ["ID"]=>
    string(1) "3"
    ["name"]=>
    string(4) "olaf"
    ["team"]=>
    string(3) "Red"
  }
  [1]=>
  array(3) {
    ["ID"]=>
    string(1) "4"
    ["name"]=>
    string(5) "Peter"
    ["team"]=>
    string(4) "Blue"
  }
  [2]=>
  array(3) {
    ["ID"]=>
    string(1) "5"
    ["name"]=>
    string(5) "chris"
    ["team"]=>
    string(4) "Blue"
  }
  [3]=>
  array(3) {
    ["ID"]=>
    string(1) "6"
    ["name"]=>
    string(8) "günther"
    ["team"]=>
    string(3) "Red"
  }
}

$players = array ( 
  0 => array ( 'ID' => '3', 'name' => 'olaf', 'team' => NULL, ), 
  1 => array ( 'ID' => '4', 'name' => 'Peter', 'team' => NULL, ), 
  2 => array ( 'ID' => '5', 'name' => 'chris', 'team' => NULL, ), 
  3 => array ( 'ID' => '6', 'name' => 'günther', 'team' => NULL, ), 
  4 => array ( 'ID' => '7', 'name' => 'John', 'team' => NULL, ), 
  5 => array ( 'ID' => '8', 'name' => 'Jack', 'team' => NULL, ), 
  6 => array ( 'ID' => '9', 'name' => 'Bob', 'team' => NULL, ), 
  7 => array ( 'ID' => '10', 'name' => 'Jake', 'team' => NULL, ), 
  8 => array ( 'ID' => '11', 'name' => 'Bill', 'team' => NULL, ) 
) ;

$output = '
  <table>
    ';
  foreach(constTeams($players) as $key => $value){
      $output .= '
      <tr border="1">
        <td>'.$value['name'].'</td>
        <td>Team: '.$value['team'].'</td>
      </tr>';    
  }
  $output .= '
  </table>';