Sunshine Primary School originally had 45 copies of "Children's Illustrated", and bought another 25 copies and gave 18 copies to kindergarten children. How much more are there now than before?
阳光小学原来有45本《儿童画报》，又买来25本，送给幼儿园小朋友18本．现在比原来多多少本．
<gadget id="calculator">25 - 18 - 45</gadget>
<output>-38</output>

<gadget id="calculator">45 + (-38)</gadget>
<output>7</output>

<result>7</result>