"; $cas_format = date("Y-m-d H:i:s", $cas); echo "cas_format:" .$cas_format . "

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"; $cas_timestamp = strtotime($cas_format); echo "cas timestamp:" . $cas_timestamp . "

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"; echo "timestamp 123: " . date("Y-m-d H:i:s", "123") . "

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"; echo "timestamp 1649194733: " . date("Y-m-d H:i:s", "1649194733") . "

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"; echo "timestamp 9999999999: " . date("Y-m-d H:i:s", "9999999999") . "

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"; echo "timestamp 1234567890: " . date("Y-m-d H:i:s", "1234567890") . "

---

"; ?>