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<?php function cmp($a, $b) { if ($a == $b) { return 0; } echo "a".$a."b".$b."\n"; return ($a > $b) ? -1 : 1; } $a = array(3, 2, 5, 6, 1); usort($a, "cmp"); foreach ($a as $key => $value) { echo "$key: $value\n"; } $b = $a; sort($b); echo "B:\n"; foreach ($a as $key => $value) { echo "$key: $value\n"; }
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
a3b2 a2b5 a3b5 a2b6 a3b6 a5b6 a2b1 0: 6 1: 5 2: 3 3: 2 4: 1 B: 0: 6 1: 5 2: 3 3: 2 4: 1
preferences:
167.43 ms | 404 KiB | 204 Q