C++中的fmax()和fmin()

fmax()和fmin()函数在cmath头文件中定义。

1. fmax()函数：此函数的语法为：

   double fmax (double x, double y);
   float fmax (float x, float y);
   long double fmax (long double x, long double y);
   

   该函数的输入是float，double或long double类型的两个值。该函数返回两个输入值中的最大值。

   以下是示例C++程序，用于显示fmax()函数：

   // CPP program to show working
   // of fmax() function.
     
   #include 
   #include 
   #include 
     
   using namespace std;
     
   int main()
   {
       double val;
     
       // Find maximum value when both the inputs
       // are positive.
       val = fmax(10.0, 1.0);
       cout << fixed << setprecision(4)
            << "fmax(10.0, 1.0) = " << val << "\n";
     
       // Find maximum value when inputs have
       // opposite sign.
       val = fmax(-10.0, 1.0);
       cout << fixed << setprecision(4)
            << "fmax(-10.0, 1.0) = " << val << "\n";
     
       // Find maximum value when both the inputs
       // are negative.
       val = fmax(-10.0, -1.0);
       cout << fixed << setprecision(4)
            << "fmax(-10.0, -1.0) = " << val << "\n";
     
       return 0;
   }
   

   输出：

   fmax(10.0, 1.0) = 10.0000
   fmax(-10.0, 1.0) = 1.0000
   fmax(-10.0, -1.0) = -1.0000
   

2. fmin()函数：此函数的语法为：

   double fmin (double x, double y);
   float fmin (float x, float y);
   long double fmin (long double x, long double y);
   

   该函数的输入是float，double或long double类型的两个值。该函数返回两个输入值中的最小值。

   下面是示例C++程序，用于显示fmin()函数：

   // CPP program to show working
   // of fmin() function.
     
   #include 
   #include 
   #include 
     
   using namespace std;
     
   int main()
   {
       double val;
     
       // Find minimum value when both the inputs
       // are positive.
       val = fmin(10.0, 1.0);
       cout << fixed << setprecision(4)
            << "fmin(10.0, 1.0) = " << val << "\n";
     
       // Find minimum value when inputs have
       // opposite sign.
       val = fmin(-10.0, 1.0);
       cout << fixed << setprecision(4)
            << "fmin(-10.0, 1.0) = " << val << "\n";
     
       // Find minimum value when both the inputs
       // are negative.
       val = fmin(-10.0, -1.0);
       cout << fixed << setprecision(4)
            << "fmin(-10.0, -1.0) = " << val << "\n";
     
       return 0;
   }
   

   输出：

   fmin(10.0, 1.0) = 1.0000
   fmin(-10.0, 1.0) = -10.0000
   fmin(-10.0, -1.0) = -10.0000
   

   注意：考虑函数的参数为不同类型的情况。在这种情况下，参数首先由函数隐式类型转换，然后返回所需的最大值/最小值。
   下面是说明这种情况的示例C++程序：

   // CPP program to show working
   // of fmin() and fmax()function
   // when input values are of
   // different data types.
     
   #include 
   #include 
   #include 
     
   using namespace std;
     
   int main()
   {
       double val;
     
       // Find minimum value when one of the inputs
       // is of type float and other is of type
       // double.
       val = fmin(10.0f, 1.0);
       cout << fixed << setprecision(4)
            << "fmin(10.0f, 1.0) = " << val << "\n";
     
       // Find maximum value when one of the inputs
       // is of type float and other is of type
       // double.
       val = fmax(10.0, -1.0f);
       cout << fixed << setprecision(4)
            << "fmax(10.0, -1.0f) = " << val << "\n";
     
       return 0;
   }
   

   输出：

   fmin(10.0f, 1.0) = 1.0000
   fmax(10.0, -1.0f) = 10.0000
   

   要从最佳影片策划和实践问题去学习，检查了C++基础课程为基础，以先进的C++和C++ STL课程基础加上STL。要完成从学习语言到DS Algo等的更多准备工作，请参阅“完整面试准备课程” 。