5人の学生を 身長・体重で ソート (関数ポインタ)

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5人の学生を 身長・体重で ソート (関数ポインタ)

PHP
<?php
$NINSU = 5;

function swap(&$x, &$y)
{
    $tmp = $x;
    $x   = $y;
    $y   = $tmp;
}

function compare_height($x, $y)
{
    if ($x["height"] > $y["height"]) return  1;
    if ($x["height"] < $y["height"]) return -1;
    return 0;
}

function compare_weight($x, $y)
{
    if ($x["weight"] > $y["weight"]) return  1;
    if ($x["weight"] < $y["weight"]) return -1;
    return 0;
}

function sort1(&$data, $n, $compare)
{
    $k = $n - 1;
    while ($k >= 0)
    {
        $j = -1;
        for ($i = 1; $i <= $k; $i++)
        {
            if ($compare($data[$i - 1], $data[$i]) > 0)
            {
                $j = $i - 1;
                swap($data[$i], $data[$j]);
            }
        }
        $k = $j;
    }
}

$data = array(
        array(name => "Sato",   height => 178, weight => 61.0),
        array(name => "Sanaka", height => 175, weight => 60.5),
        array(name => "Takao",  height => 173, weight => 80.0),
        array(name => "Mike",   height => 165, weight => 72.0),
        array(name => "Masaki", height => 179, weight => 77.5)
        );

print "ソート前:\n";
for ($i = 0; $i < $NINSU; $i++)
{
    printf("%2d:%-8s%4d%6.1f\n", $i + 1, $data[$i]["name"], $data[$i]["height"], $data[$i]["weight"]);
}
print "\n";

sort1($data, $NINSU, "compare_height");

print "身長でソート後:\n";
for ($i = 0; $i < $NINSU; $i++)
{
    printf("%2d:%-8s%4d%6.1f\n", $i + 1, $data[$i]["name"], $data[$i]["height"], $data[$i]["weight"]);
}
print "\n";

sort1($data, $NINSU, "compare_weight");

print "体重でソート後:\n";
for ($i = 0; $i < $NINSU; $i++)
{
    printf("%2d:%-8s%4d%6.1f\n", $i + 1, $data[$i]["name"], $data[$i]["height"], $data[$i]["weight"]);
}
?>

実行結果

L:\>php lesson_12_097.php
ソート前:
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

身長でソート後:
1:Mike 165 72.0
2:Takao 173 80.0
3:Sanaka 175 60.5
4:Sato 178 61.0
5:Masaki 179 77.5

体重でソート後:
1:Sanaka 175 60.5
2:Sato 178 61.0
3:Mike 165 72.0
4:Masaki 179 77.5
5:Takao 173 80.0