#include <iostream> using namespace std; //在此处补充你的代码 class Derived : public Base { public: int Bar(char x) { return (int)(-x); } int Bar(int x) { return (x / 2);

缺少代码结尾的大括号和分号。完整代码应该是这样的：

#include <iostream>
using namespace std;

class Base {
public:
    Base() {}
    virtual ~Base() {}
};

class Derived : public Base {
public:
    int Bar(char x) {
        return (int)(-x);
    }
    int Bar(int x) {
        return (x / 2);
    }
};