If (a) represents the largest prime number smaller than a, (a) represents the smallest prime number larger than a, {a} represents the number closest to a among the smallest prime number larger than a and the largest prime number smaller than a, then 25+20 What is the result of -(35)+{49}?
若用(a)表示小于a的最大质数，(a)表示大于a的最小质数，{a}表示在大于a的最小质数和小于a的最大质数之中最接近a的数，那么25+20-(35)+{49}的结果是多少．
<gadget id="calculator">25 + 17 + 37 + 47</gadget>
<output>126</output>

<result>126</result>