#include <iostream> #include <unistd.h> using namespace std; class BaseCalculator { public: int m_A; int m_B; // write your code here...... virtual int getResult() = 0; }; // 加法计算器类 class AddCalculator : public BaseCalculator { // write your code here...... int getResult() { return (m_A + m_B); } }; // 减法计算器类 class SubCalculator : public BaseCalculator { // write your code here...... int getResult() { return (m_A - m_B); } }; int main() { BaseCalculator* cal = new AddCalculator; cal->m_A = 10; cal->m_B = 20; cout << cal->getResult() << endl; delete cal; cal = new SubCalculator; cal->m_A = 20; cal->m_B = 10; cout << cal->getResult() << endl; delete cal; return 0; }