$list = [
['score1' => 'A', 'score2' => 'C'],
['score1' => 'D', 'score2' => 'B'],
['score1' => 'B', 'score2' => 'B'],
['score1' => 'A', 'score2' => 'B'],
['score1' => 'C', 'score2' => 'C'],
['score1' => 'B', 'score2' => 'D'],
['score1' => 'B', 'score2' => 'B'],
['score1' => 'A', 'score2' => 'B'],
['score1' => 'A', 'score2' => 'A'],
['score1' => 'D', 'score2' => 'D'],
];
$newlist = array_filter($list, function($itm) {
return $itm['score1'] == $itm['score2'];
});
var_dump(count($newlist));
$list = [
['score1' => 'A', 'score2' => 'C'],
['score1' => 'D', 'score2' => 'B'],
['score1' => 'B', 'score2' => 'B'],
['score1' => 'A', 'score2' => 'B'],
['score1' => 'C', 'score2' => 'C'],
['score1' => 'B', 'score2' => 'D'],
['score1' => 'B', 'score2' => 'B'],
['score1' => 'A', 'score2' => 'B'],
['score1' => 'A', 'score2' => 'A'],
['score1' => 'D', 'score2' => 'D'],
];
foreach($list as $v) {
$a[] = $v['score1'];
$b[] = $v['score2'];
}
print_r(array_intersect_assoc($a,$b));
Array
(
[2] => B
[4] => C
[6] => B
[8] => A
[9] => D
)
