拆分数组，随机随机播放

Question

Does anyone know how I can split an array into groups of two, without any group(team in this case) meeting eachother again till running out of possibilities?

array [ 0, 1, 2, 3, 4, 5 ]

Answer 1

This is definitely not the optimal way to do this, please optimize it yourself (this will work for only even number of teams):

 <?php
    $allTeams = [0,1,2,3,4,5];
    $everyGames = [];//Append team matches to this
    foreach($allTeams as $team1){
        foreach($allTeams as $team2){
            if (!in_array([$team2, $team1], $everyGames)
                && $team2 !== $team1) {
                $everyGames[] = [$team1, $team2];
            }               

        }
    }
    $copyOfEveryGames = $everyGames;
    $needToLoopAgain = true;
    while($needToLoopAgain ){
        $allRounds = [];
        $needToLoopAgain = false;
        $everyGames  = $copyOfEveryGames;
        shuffle($everyGames);//Shuffle it for the random array
        while(count($everyGames) > 0){
            $allMatches = [];
            $tempEveryGames = $everyGames;
            for($i = 0; $i < count($allTeams) / 2; $i++){
                foreach($tempEveryGames as $key => $game){
                    if(!(in_array_r($game[0], $allMatches) || in_array_r($game[1], $allMatches))){
                        $allMatches[] = $game;
                        unset($tempEveryGames[$key]);
                        break;
                    }
                }
            }   
            if(count($allMatches) === count($allTeams) / 2){
                $everyGames = $tempEveryGames ;

                $allRounds[] = $allMatches;
            }else{
                $needToLoopAgain = true;
                break;
            }
        }
        if(count($allRounds) !== count($allTeams) -1){
            $needToLoopAgain = true;
        }
    }

    //Display Example
    foreach($allRounds as $round){
        print_r($round);
        echo "<br>";
    }
    /*
    Example Output:
    Array ( [0] => Array ( [0] => 0 [1] => 3 ) 
            [1] => Array ( [0] => 1 [1] => 4 ) 
            [2] => Array ( [0] => 2 [1] => 5 ) ) 
    Array ( [0] => Array ( [0] => 0 [1] => 2 ) 
            [1] => Array ( [0] => 4 [1] => 5 ) 
            [2] => Array ( [0] => 1 [1] => 3 ) ) 
    Array ( [0] => Array ( [0] => 1 [1] => 2 ) 
            [1] => Array ( [0] => 3 [1] => 4 ) 
            [2] => Array ( [0] => 0 [1] => 5 ) ) 
    Array ( [0] => Array ( [0] => 1 [1] => 5 ) 
            [1] => Array ( [0] => 0 [1] => 4 ) 
            [2] => Array ( [0] => 2 [1] => 3 ) ) 
    Array ( [0] => Array ( [0] => 0 [1] => 1 ) 
            [1] => Array ( [0] => 2 [1] => 4 ) 
            [2] => Array ( [0] => 3 [1] => 5 ) ) 
    */

    //Copied from http://stackoverflow.com/questions/4128323/in-array-and-multidimensional-array
    function in_array_r($needle, $haystack, $strict = false) {
        foreach ($haystack as $item) {
            if (($strict ? $item === $needle : $item == $needle) || (is_array($item) && in_array_r($needle, $item, $strict))) {
                return true;
            }
        }

        return false;
    }

?>