The Maritime Museum sold 144 tickets in the morning on Saturday, 187 in the afternoon, 256 in the morning and 213 in the afternoon on Sunday. How many tickets were sold in these two days?
海洋博物馆星期六上午卖出门票144张，下午卖出187张，星期天上午卖出256张，下午卖出213张，这两天一共卖出多少张门票？
<gadget id="calculator">144 + 187</gadget>
<output>331</output>

<gadget id="calculator">256 + 213</gadget>
<output>469</output>

<gadget id="calculator">331 + 469</gadget>
<output>800</output>

<result>800</result>