【问题】 阅读下面内容,并将问题解决过程补充完整:
$\frac{1}{{\sqrt{2}+1}}=\frac{{1×(\sqrt{2}-1)}}{{(\sqrt{2}+1)(\sqrt{2}-1)}}=\sqrt{2}-1$;
$\frac{1}{{\sqrt{3}+\sqrt{2}}}=\frac{{1×(\sqrt{3}-\sqrt{2})}}{{(\sqrt{3}+\sqrt{2})(\sqrt{3}-\sqrt{2})}}=\sqrt{3}-\sqrt{2}$;
$\ldots $

阅读下面内容,并将问题解决过程补充完整:
$\frac{1}{{\sqrt{2}+1}}=\frac{{1×(\sqrt{2}-1)}}{{(\sqrt{2}+1)(\sqrt{2}-1)}}=\sqrt{2}-1$;
$\frac{1}{{\sqrt{3}+\sqrt{2}}}=\frac{{1×(\sqrt{3}-\sqrt{2})}}{{(\sqrt{3}+\sqrt{2})(\sqrt{3}-\sqrt{2})}}=\sqrt{3}-\sqrt{2}$;
$\ldots $
$\frac{1}{{\sqrt{100}+\sqrt{99}}}=\frac{{1×(\sqrt{100}-\sqrt{99})}}{{(\sqrt{100}+\sqrt{99})(\sqrt{100}-\sqrt{99})}}=\sqrt{100}-\sqrt{99}$.
由此,我们可以解决下面问题:$S=1+\frac{1}{{\sqrt{2}}}+\frac{1}{{\sqrt{3}}}+\ldots +\frac{1}{{\sqrt{100}}}$,请求出$S$的整数部分.
解:$S=1+\frac{1}{{\sqrt{2}}}+\frac{1}{{\sqrt{3}}}+\ldots +\frac{1}{{\sqrt{100}}}=\frac{2}{{1+1}}+\frac{2}{{\sqrt{2}+\sqrt{2}}}+\frac{2}{{\sqrt{3}+\sqrt{3}}}+\ldots +\frac{1}{{\sqrt{100}+\sqrt{100}}}$
$ \lt \frac{2}{{1+1}}+\frac{2}{{1+\sqrt{2}}}+\frac{2}{{\sqrt{2}+\sqrt{3}}}+\ldots +\frac{2}{{\sqrt{99}+\sqrt{100}}}=1+2(\sqrt{2}-1+\sqrt{3}-\sqrt{2}+\ldots +\sqrt{100}-\sqrt{99})=19$;
$S=1+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+\ldots +\frac{1}{\sqrt{100}}=\frac{2}{1+1}+\frac{2}{\sqrt{2}+\sqrt{2}}+\frac{2}{\sqrt{3}+\sqrt{3}}+\ldots +\frac{2}{\sqrt{100}+\sqrt{100}} \gt \_\_\_\_\_\_.$
$\therefore S$的整数部分是______.

正确答案:$S=1+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+\cdots +\frac{1}{\sqrt{100}}=\frac{2}{1+1}+\frac{2}{\sqrt{2}+\sqrt{2}}+\cdots +\frac{2}{\sqrt{100}+\sqrt{100}} \lt \frac{2}{1+1}+\frac{2}{1+\sqrt{2}}+\frac{2}{\sqrt{2}+\sqrt{3}}+\cdots +\frac{2}{\sqrt{99}+\sqrt{1

题目解析:

根据题中给出的计算方法进行计算求解即可.

点评:

此题考查了估算无理数的大小,正确估算出$S$的整数部分是$18$是解题的关键.