c ++错误中的struct initialization

Question

我是c ++的新手,我在visual studio c ++中运行以下代码

    struct bob
    {
       double a,b;      
       bob(double a,double b);
    }

    int main()
    {
        bob z(2.2,5.6);
        cout<<z.a<<endl;
        keep_window_open();
        return 0;
    }     

当我运行此代码时,我收到以下错误:

错误1错误LNK2019:函数_main C:\ drives\Comp-Mech\programming\VS中引用了未解析的外部符号"public:__thiscall bob :: bob(double,double)"(?? 0bob @@ QAE @NN @ Z)\C++\projects\E1\E1.obj E1

Answer 1

你需要实现你的类bob的构造函数:

 bob::bob(double a,double b) : a(a), b(b) {}