The locksmith is matching the locks. Now there are 5 keys and 5 locks, which are exactly the same, but one key can only open one lock. I don’t know which key can open which lock. It takes at least a few tries to match all the locks. ?
锁匠配锁，现在有5把钥匙和5把锁，一模一样，但一把钥匙只能开一把锁，不知道哪把钥匙开哪把锁，问至少要试几次才能配好所有的锁？
<gadget id="calculator">4 + 3 + 2 + 1</gadget>
<output>10</output>

<result>10</result>