Xcode错误"没有用于调用'max'的匹配函数"

Question

这是我正在使用的声明,但它表示没有匹配函数来调用'max'

max((used_minutes-Included_Minutes)*extra_charge,0) 

任何帮助,将不胜感激.

编辑

码

 int used_minutes; const int Included_Minutes = 300;
 double total_charge, extra_charge;
 cout << "Enter the number of phone call minutes: ";
 cin >> used_minutes;
 cout <<"Number of phone call minutes used - included in the base plan: " << min(used_minutes,Included_Minutes) << endl;
 cout <<"Number of phone call minutes used - not included in the base plan: "<< max(used_minutes-Included_Minutes,0) << endl;
 extra_charge = 0.10;
 cout <<"Cost of excess phone call minutes: $"<<fixed << setprecision(2) << max(used_minutes-Included_Minutes)*extra_charge, 0) <<endl;

Answer 1

max()要求第一个和第二个参数属于同一类型.extra_charge是double,导致第一个和第二个参数具有不同的类型.尝试:

max((used_minutes-Included_Minutes)*extra_charge,0.0)