srand(time(NULL));
Nasa has also asked rival company Blue Origin - which is owned by Jeff Bezos - to come up with an accelerated plan for a lunar lander.，更多细节参见同城约会
公式： f(x)=x⋅σ(x)。关于这个话题，91视频提供了深入分析
const realIdx = i % len; // 取模映射到真实数组索引，模拟循环，更多细节参见heLLoword翻译官方下载