C语言书籍的课后答案-Ch_.docVIP

Chapter 8 Friends ， Overloaded Operators，and Arrays in Classes 1. Solutions to and Remarks on Selected Programming Problems 1. Modify Money class. No solution is provided for this exercise. 2. Implement constructors and overload , , +, and * for class Pair. //Chapter 8Programming Problem #2 //Enhance Self Test Problem 17 by completing the // overloading of operator and for class Pair // Implement: // The default constructor // A one int parameter constructor that // sets the first member to the parameter // and the second to 0. // A two int parameter constructor. // Overload * on a Pair and an int // (x, y)*c = (x*c, y*c) // Overload + on two objects of type Pair. // (a, b) + (c, d) = (a + c, b + d) #include iostream using namespace std; class Pair { public: Pair(); Pair(int first, int second); Pair(int first); int accessFirst(); int accessSecond(); // other members and friends friend Pair operator+(const Pair, const Pair); friend Pair operator*(const Pair, int); friend istream operator (istream, Pair); friend ostream operator (ostream, const Pair); private: int f; int s; }; int main() { Pair x; Pair y(2,3); Pair z(4); cout x.accessFirst() endl; cout x.accessSecond() endl; cout y.accessFirst() endl; cout y.accessSecond() endl; cout z.accessFirst() endl; cout z.accessSecond() endl; cout endl; cout x x endl y y endl z z endl endl; x = y + z; cout y + z x endl; cout y * 2 y * 2 endl; return 0; } Pair operator+(const Pair lhs, const Pair rhs) { return Pair(lhs.f + rhs.f, lhs.s + rhs.s); } Pair operator*(const Pair lhs, int rhs) { return Pair(lhs.f * rhs, lhs.s * rhs); } istream operator (istream ins, Pair second) { char ch; ins ch; // discard init ( ins second.f; ins ch; // discard comma , ins second.s; ins ch; // discard final ( return ins; } ostream operator (ostream outs, const Pair second) { outs (; outs second.f; outs ,