c++ 类的数据成员初始化

class First{public:int num = 0;//错误const int num1 = 0;//错误static int num2 = 0;//错误static const int num3 = 0;//正确，只有静态常量整型数据成员才可以在类中初始化string str = "0";//错误const string str1 = "0";//错误static string str2 = "0";//错误static const string str3 = "0";//错误float fnum = 0;//错误const float fnum1 = 0;//错误static float fnum2 = 0;//错误static const float fnum3 = 0;//错误};

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