text: #include <iostream>
  #include <cmath>
  #include <ctime>
  
  using namespace std;
  
  int main() {
      short s = 10;
      int i = -10000;
      long l = 100000;
      float f = 230.45;
      double d = 200.43;
  
      cout << sin(d) << endl;
      cout << abs(i) << endl;
      cout << log(s) << endl;
      cout << pow(s, 2) << endl;
      cout << hypot(3, 4) << endl;
      cout << floor(d) << endl;
      cout << sqrt(f) << endl;
  
      //生成随机数,设置种子
      srand((unsigned) time(NULL));
      //生成10个随机数
      int r;
      for (int j = 0; j < 10; j++) {
          r = rand();
          cout << "random " << r << endl;
      }
      return 0;
  }