Four different natural numbers A, B, C, and D are arranged in a row in order from large to small, and any two of them are differenced (largely reduced) to obtain 5 different differences: 7, 11, 14, 18, 25. Find the value of BC.
四个互不相同的自然数A、B、C、D是按从大到小的顺序排成一排，将其中任意两个数做差(大减小)以得到5个不同的差：7，11，14，18，25．求B-C的值．
<gadget id="calculator">18 + 14</gadget>
<output>32</output>

<gadget id="calculator">32 - 25</gadget>
<output>7</output>

<result>7</result>