单独使用 PHP 的完美排名

Question

在我试图找到带领带的完美排名解决方案时，我一直无法给出正确的排名。代码将解释我想要更好地实现的目标：

我有以下数组：

$standings = array(
    'player_1' => 30,
    'player_2' => 26,
    'player_3' => 28,
    'player_9' => 28
);

现在为了对它进行并列排名，我有以下功能：

function setRanking($standings) {
    $rankings = array();
    arsort($standings);
    $rank = 1;
    $tie_rank = 0;
    $prev_score = -1;
    foreach ($standings as $name => $score) {
        if ($score != $prev_score) {  //this score is not a tie
            $count = 0;
            $prev_score = $score; 
            $rankings[$name] = array('score' => $score, 'rank' => $rank);
        } else { //this score is a tie
            $prev_score = $score;
            if ($count++ == 0) {
                $tie_rank = $rank - 1;
            }
            $rankings[$name] = array('score' => $score, 'rank' => $tie_rank);
        }
        $rank++;
    }
    return $rankings;
}
echo '<pre>';
print_r(setRanking($standings));

输出：

Array
(
    [player_1] => Array
        (
            [score] => 30
            [rank] => 1
        )

    [player_3] => Array
        (
            [score] => 28
            [rank] => 2
        )

    [player_9] => Array
        (
            [score] => 28
            [rank] => 2
        )

    [player_2] => Array
        (
            [score] => 26
            [rank] => 4
        )

)

预期输出：

Array
(
    [player_1] => Array
        (
            [score] => 30
            [rank] => 1
        )

    [player_3] => Array
        (
            [score] => 28
            [rank] => 2
        )

    [player_9] => Array
        (
            [score] => 28
            [rank] => 2
        )

    [player_2] => Array
        (
            [score] => 26
            [rank] => 3
        )

)

问题是它将排名打印为 1,2,2,4，而根据我的假设它应该打印 1,2,2,3。那么它如何打印 1,2,2,3 呢？哪里可能出错？任何帮助表示赞赏。谢谢。

Answer 1

只需更改您的 else 块，您不会递减 $rank 值，因此它保持与现在相同的值。您只需执行 $rank - 1 即可将其减去 1 存储在变量中而不更改主值。

foreach ($standings as $name => $score) {
    if ($score != $prev_score) {  //this score is not a tie
        $count = 0;
        $prev_score = $score; 
        $rankings[$name] = array('score' => $score, 'rank' => $rank);
    } else { //this score is a tie
        $prev_score = $score;
        $rank--; // Decrements here
        if ($count++ == 0) {
            $tie_rank = $rank;
        }
        $rankings[$name] = array('score' => $score, 'rank' => $tie_rank);
    }
    $rank++;
}
return $rankings;

单独使用 PHP 的完美排名

Perfect Ranking with ties using PHP alone

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