Операторни функции за въвеждане и извеждане

lectures/1/rational/main.cpp

@@ -45,14 +45,16 @@ void testRational() {
     Rational q = Rational(5, 6);
     q.printnl();
     std::cout << q.toDouble() << std::endl;
-    q.read();
+    //q.read();
+    std::cin >> q;
 
     q.printnl();
-    r.print();
-    std::cout << " * ";
-    q.print();
-    std::cout << " = ";
-    multiply(r, q).printnl();
+    // r.print();
+
+    std::cout << r << " * " << q << " = " << multiply(r, q) << std::endl;
+ //   q.print();
+//  std::cout << " = ";
+ //   multiply(r, q).printnl();
 
     r.print();
     std::cout << " + ";

lectures/1/rational/rational.cpp

@@ -70,4 +70,15 @@ bool lessThan(Rational const& p, Rational const& q) {
 
 inline bool Rational::equals(Rational const& p) const {
     return numer == p.numer && denom == p.denom;
-}
+}
+
+std::ostream& operator<<(std::ostream& os, Rational const& r) {
+    return os << r.numer << '/' << r.denom;
+}
+
+std::istream& operator>>(std::istream& is, Rational& r) {
+    char c;
+    is >> r.numer >> c >> r.denom;
+    r.normalize();
+    return is;
+}

lectures/1/rational/rational.hpp

@@ -3,6 +3,8 @@
 #ifndef __RATIONAL_HPP
 #define __RATIONAL_HPP
 
+#include <iostream>
+
 class Rational {
 private:
     // ниво 0: представяне
@@ -35,6 +37,13 @@ class Rational {
 
     // ниво 1: селектор за сравнение
     bool equals(Rational const& p) const;
+
+    // ниво 1: въвеждане и извеждане
+    // !!! std::ostream& operator<<(std::ostream&) const;
+
+    friend std::ostream& operator<<(std::ostream&, Rational const&);
+    // { return ... }
+    friend std::istream& operator>>(std::istream&, Rational&);
 };
 
 // ниво 2: аритметични операции за умножение и събиране