The sum of a number plus 2 is 1 more than the smallest three-digit number. What is this number?
一个数加2的和比最小的三位数多1，这个数是多少．
<gadget id="calculator">1 - 2</gadget>
<output>-1</output>

<gadget id="calculator">100 + (-1)</gadget>
<output>99</output>

<result>99</result>