How can I translate this PHP into C# code?

Question

I am trying to create a tournament bracket system in my C# asp.net core application. I found this Tournament bracket placement algorithm post and RWC's answer is what I need because it also includes byes.

The problem I'm having is translating this piece of code to c#:

<?php

define('NUMBER_OF_PARTICIPANTS', 16);

$participants = range(1,NUMBER_OF_PARTICIPANTS);
$bracket = getBracket($participants);
var_dump($bracket);

function getBracket($participants)
{
    $participantsCount = count($participants);  
    $rounds = ceil(log($participantsCount)/log(2));
    $bracketSize = pow(2, $rounds);
    $requiredByes = $bracketSize - $participantsCount;

    echo sprintf('Number of participants: %d<br/>%s', $participantsCount, PHP_EOL);
    echo sprintf('Number of rounds: %d<br/>%s', $rounds, PHP_EOL);
    echo sprintf('Bracket size: %d<br/>%s', $bracketSize, PHP_EOL);
    echo sprintf('Required number of byes: %d<br/>%s', $requiredByes, PHP_EOL);    

    if($participantsCount < 2)
    {
        return array();
    }

    $matches = array(array(1,2));

    for($round=1; $round < $rounds; $round++)
    {
        $roundMatches = array();
        $sum = pow(2, $round + 1) + 1;
        foreach($matches as $match)
        {
            $home = changeIntoBye($match[0], $participantsCount);
            $away = changeIntoBye($sum - $match[0], $participantsCount);
            $roundMatches[] = array($home, $away);
            $home = changeIntoBye($sum - $match[1], $participantsCount);
            $away = changeIntoBye($match[1], $participantsCount);
            $roundMatches[] = array($home, $away);
        }
        $matches = $roundMatches;
    }

    return $matches;

}

function changeIntoBye($seed, $participantsCount)
{
    //return $seed <= $participantsCount ?  $seed : sprintf('%d (= bye)', $seed);  
    return $seed <= $participantsCount ?  $seed : null;
}

?>

I have tried translating each piece of PHP line to C# equivalent. However, this snippet is what stopped me at my tracks:


for($round=1; $round < $rounds; $round++)
    {
        $roundMatches = array();
        $sum = pow(2, $round + 1) + 1;
        foreach($matches as $match)
        {
            $home = changeIntoBye($match[0], $participantsCount);
            $away = changeIntoBye($sum - $match[0], $participantsCount);
            $roundMatches[] = array($home, $away);
            $home = changeIntoBye($sum - $match[1], $participantsCount);
            $away = changeIntoBye($match[1], $participantsCount);
            $roundMatches[] = array($home, $away);
        }
        $matches = $roundMatches;
    }

I don't understand what $roundMatches[] is trying to accomplish. Is it recreating the array? Is it setting a pointer? No idea. The C# version I wrote gives me wrong seeding number fo each match.

public Dictionary<int, string> getBracket(Dictionary<int, string> participants)
        {
            Dictionary<int, string> orderedParticipants = new Dictionary<int, string>();
            var count = participants.Count;
            var rounds = Math.Ceiling(Math.Log(count) / Math.Log(2));
            var bracketSize = Math.Pow(2, rounds);
            var requiredByes = bracketSize - count;


            string p = $"Number of participants: {count}";
            string r = $"Number of rounds: {rounds}";
            string b = $"Bracket size: {bracketSize}";
            string byes = $"Required number of byes: {requiredByes}";

            List<List<int>> matches = new List<List<int>>();
            matches.Add(new List<int>() {1, 2});


            for (int round = 1; round < rounds; round++)
            {
                List<int> roundMatches = new List<int>();

                var sum = (int)Math.Pow(2, round + 1) + 1;

                foreach (var match in matches)
                {
                    var home = changeIntoBye(match[0], count);
                    var away = changeIntoBye(sum - match[0], count);
                    roundMatches = new List<int> {home.Value, away.Value};
                    //roundMatches
                    home = changeIntoBye(sum - match[1], count);
                    away = changeIntoBye(match[1], count);
                }

                matches.Add(roundMatches);
            }


            return orderedParticipants;
        }

`$roundMatches[] = array($home, $away);` is the same as `array_push($roundMatches, array($home, $away));` — Patrick Q, Aug 21 '19 at 11:59

score 0 · Accepted Answer · answered Aug 21 '19 at 12:06

0

it is basically the same as array_push

example

$var[] = "element 1";
$var[] = "element 2";

print_r($var);

will output Array ( [0] => element 1 [1] => element 2 )

if you want to do the same in c# i think you have to use myList.add("element")

answered Aug 21 '19 at 12:06

Nathan Kolpa

89
10

Quite odd notation to push elements to an array. Regardless, this helped me fix my issue. Thanks. Marked as answer – pejno Aug 21 '19 at 12:12
you have click the star button to mark it as answer, dummy ;) – Nathan Kolpa Aug 21 '19 at 13:14
1

hahaha apologies. Done it now :) – pejno Aug 21 '19 at 13:21

How can I translate this PHP into C# code?

1 Answers1