There are 195 books in the library, 58 books were lent out today, and 45 books were returned. How many books are there in the library now?
图书室有图书195本，今天借出58本，还回45本．现在图书室有图书多少本．
<gadget id="calculator">195 - 58</gadget>
<output>137</output>

<gadget id="calculator">137 + 45</gadget>
<output>182</output>

<result>182</result>