The age of the elder brother 5 years ago is equal to that of the younger brother 7 years later, and the sum of the ages of the elder brother 4 years later and the age of the younger brother 3 years ago is 35 years old. How old is brother?
哥哥5年前与弟弟7年后的年龄相等，哥哥4年后与弟弟3年前的年龄和是35岁．哥哥今年多少岁．
<gadget id="calculator">35 - 5 - 7 - 4</gadget>
<output>19</output>

<gadget id="calculator">3 + 19</gadget>
<output>22</output>

<gadget id="calculator">1 + 1</gadget>
<output>2</output>

<gadget id="calculator">22 / 2</gadget>
<output>11</output>

<gadget id="calculator">11 + 5 + 7</gadget>
<output>23</output>

<result>23</result>