C++庫函數收集

1. 數值類型極限值

std::numeric_limits<double>::max();

2. 隨機數發生函數
   2.1 均勻分佈

The  drand48() and erand48() functions return nonnegative double-preci‐
       sion floating-point values  uniformly  distributed  over  the  interval
       [0.0, 1.0).