Xiao Ming has some stamps, and gave 12 to Xiao Hong, and he collected 18 more, and now there are exactly 50 stamps with him. How many copies did he have?
小明有一些邮票，送给小红12张，他又收集了18张，现在他身边正好50张．他原来有多少张？
<gadget id="calculator">50 - 18</gadget>
<output>32</output>

<gadget id="calculator">12 + 32</gadget>
<output>44</output>

<result>44</result>