There are 80 locks whose keys are messed up. What is the maximum number of attempts to get each lock to have its own key?
有80把锁的钥匙搞乱了，为了使每把锁都配上自己的钥匙，至多要试多少次？
<gadget id="calculator">79 + 1</gadget>
<output>80</output>

<gadget id="calculator">79 / 2</gadget>
<output>79/2 = around 39.5</output>

<gadget id="calculator">80 * (79/2)</gadget>
<output>3_160</output>

<result>3_160</result>