module10.lst

Programs for the book Advanced Engineering Mathematics using MATLAB, 2ndEd.

listing 1
// A simple class hierarchy. 
 
#include <iostream> 
#include <cstring> 
using namespace std; 
 
// A class for two-dimensional objects. 
class TwoDShape { 
public: 
  double width; 
  double height; 
 
  void showDim() { 
    cout << "Width and height are " << 
             width << " and " << height << "\n"; 
  } 
}; 
 
// Triangle is derived from TwoDShape. 
class Triangle : public TwoDShape { 
public: 
  char style[20]; 
   
  double area() { 
    return width * height / 2; 
  } 
 
  void showStyle() { 
    cout << "Triangle is " << style << "\n"; 
  } 
}; 
 
int main() { 
  Triangle t1; 
  Triangle t2; 
 
  t1.width = 4.0; 
  t1.height = 4.0; 
  strcpy(t1.style, "isosceles"); 
 
  t2.width = 8.0; 
  t2.height = 12.0; 
  strcpy(t2.style, "right"); 
 
  cout << "Info for t1:\n"; 
  t1.showStyle(); 
  t1.showDim(); 
  cout << "Area is " << t1.area() << "\n"; 
 
  cout << "\n"; 
  cout << "Info for t2:\n"; 
  t2.showStyle(); 
  t2.showDim(); 
  cout << "Area is " << t2.area() << "\n"; 
 
  return 0; 
}

listing 2
// A derived class of TwoDShape for rectangles. 
class Rectangle : public TwoDShape { 
public: 
  bool isSquare() { 
    if(width == height) return true; 
    return false; 
  } 
   
  double area() { 
    return width * height; 
  } 
};

listing 3
// Access to private members is not granted to derived classes. 
 
class TwoDShape { 
  // these are now private 
  double width;   
  double height; 
public: 
  void showDim() { 
    cout << "Width and height are " << 
             width << " and " << height << "\n"; 
  } 
}; 
 
// Triangle is derived from TwoDShape. 
class Triangle : public TwoDShape { 
public: 
  char style[20]; 
   
  double area() { 
    return width * height / 2; // Error! Can't access. 
  } 
 
  void showStyle() { 
    cout << "Triangle is " << style << "\n"; 
  } 
};

listing 4
// Access private data through accessor functions. 
 
#include <iostream> 
#include <cstring> 
using namespace std; 
 
// A class for two-dimensional objects. 
class TwoDShape { 
  // these are private 
  double width; 
  double height; 
public: 
 
  void showDim() { 
    cout << "Width and height are " << 
             width << " and " << height << "\n"; 
  } 
 
  // accessor functions 
  double getWidth() { return width; } 
  double getHeight() { return height; } 
  void setWidth(double w) { width = w; } 
  void setHeight(double h) { height = h; } 
}; 
 
// Triangle is derived from TwoDShape. 
class Triangle : public TwoDShape { 
public: 
  char style[20]; 
   
  double area() { 
    return getWidth() * getHeight() / 2; 
  } 
 
  void showStyle() { 
    cout << "Triangle is " << style << "\n"; 
  } 
}; 
 
int main() { 
  Triangle t1; 
  Triangle t2; 
 
  t1.setWidth(4.0); 
  t1.setHeight(4.0); 
  strcpy(t1.style, "isosceles"); 
 
  t2.setWidth(8.0); 
  t2.setHeight(12.0); 
  strcpy(t2.style, "right"); 
 
  cout << "Info for t1:\n"; 
  t1.showStyle(); 
  t1.showDim(); 
  cout << "Area is " << t1.area() << "\n"; 
 
  cout << "\n"; 
  cout << "Info for t2:\n"; 
  t2.showStyle(); 
  t2.showDim(); 
  cout << "Area is " << t2.area() << "\n"; 
 
  return 0; 
}

listing 5
// Demonstrate public inheritance. 
 
#include <iostream> 
using namespace std; 
 
class B { 
  int i, j; 
public: 
  void set(int a, int b) { i = a; j = b; } 
  void show() { cout << i << " " << j << "\n"; } 
}; 
 
class D : public B { 
  int k; 
public: 
  D(int x) { k = x; } 
  void showk() { cout << k << "\n"; } 
 
  // i = 10; // Error! i is private to B and access is not allowed. 
}; 
 
int main() 
{ 
  D ob(3); 
 
  ob.set(1, 2); // access member of base class 
  ob.show();    // access member of base class 
 
  ob.showk();   // uses member of derived class 
 
  return 0; 
}

listing 6
// Use private inheritance. This program won't compile. 
 
#include <iostream> 
using namespace std; 
 
class B { 
  int i, j; 
public: 
  void set(int a, int b) { i = a; j = b; } 
  void show() { cout << i << " " << j << "\n"; } 
}; 
 
// Public elements of B become private in D. 
class D : private B { 
  int k; 
public: 
  D(int x) { k = x; } 
  void showk() { cout << k << "\n"; } 
}; 
 
int main() 
{ 
  D ob(3); 
 
  ob.set(1, 2); // Error, can't access set() 
  ob.show();    // Error, can't access show() 
 
  return 0; 
}

listing 7
// Demonstrate protected members. 
 
#include <iostream> 
using namespace std; 
 
class B { 
protected: 
  int i, j; // private to B, but accessible to D 
public: 
  void set(int a, int b) { i = a; j = b; } 
  void show() { cout << i << " " << j << "\n"; } 
}; 
 
class D : public B { 
  int k; 
public: 
  // D may access B's i and j 
  void setk() { k = i*j; } 
 
  void showk() { cout << k << "\n"; } 
}; 
 
int main() 
{ 
  D ob; 
 
  ob.set(2, 3); // OK, set() is public in B 
  ob.show();    // OK, show is public B 
 
  ob.setk(); 
  ob.showk(); 
 
  return 0; 
}

listing 8
// Add a constructor to Triangle. 
 
#include <iostream> 
#include <cstring> 
using namespace std; 
 
// A class for two-dimensional objects. 
class TwoDShape { 
  // these are private 
  double width; 
  double height; 
public: 
  void showDim() { 
    cout << "Width and height are " << 
             width << " and " << height << "\n"; 
  } 
 
  // accessor functons 
  double getWidth() { return width; } 
  double getHeight() { return height; } 
  void setWidth(double w) { width = w; } 
  void setHeight(double h) { height = h; } 
}; 
 
// Triangle is derived from TwoDShape. 
class Triangle : public TwoDShape { 
  char style[20]; // now private 
public: 
 
  // Constructor for Triangle. 
  Triangle(char *str, double w, double h) { 
   // Initialize the base class portion. 
    setWidth(w); 
    setHeight(h); 
 
    // Initialize the derived class portion. 
    strcpy(style, str); 
  } 
   
  double area() { 
    return getWidth() * getHeight() / 2; 
  } 
 
  void showStyle() { 
    cout << "Triangle is " << style << "\n"; 
  } 
}; 
 
int main() { 
  Triangle t1("isosceles", 4.0, 4.0); 
  Triangle t2("right", 8.0, 12.0); 
 
  cout << "Info for t1:\n"; 
  t1.showStyle(); 
  t1.showDim(); 
  cout << "Area is " << t1.area() << "\n"; 
 
  cout << "\n"; 
  cout << "Info for t2:\n"; 
  t2.showStyle(); 
  t2.showDim(); 
  cout << "Area is " << t2.area() << "\n"; 
 
  return 0; 
}

listing 9
// Add a constructor to TwoDShape. 
 
#include <iostream> 
#include <cstring> 
using namespace std; 
 
// A class for two-dimensional objects. 
class TwoDShape { 
  // these are private 
  double width; 
  double height; 
public: 
 
  // Constructor for TwoDShape. 
  TwoDShape(double w, double h) { 
    width = w; 
    height = h; 
  } 
 
  void showDim() { 
    cout << "Width and height are " << 
             width << " and " << height << "\n"; 
  } 
 
  // accessor functions 
  double getWidth() { return width; } 
  double getHeight() { return height; } 
  void setWidth(double w) { width = w; } 
  void setHeight(double h) { height = h; } 
}; 
 
// Triangle is derived from TwoDShape. 
class Triangle : public TwoDShape { 
  char style[20]; // now private 
public: 
 
  // Constructor for Triangle. 
  Triangle(char *str, double w, 
           double h) : TwoDShape(w, h) { 
    strcpy(style, str); 
  } 
   
  double area() { 
    return getWidth() * getHeight() / 2; 
  } 
 
  void showStyle() { 
    cout << "Triangle is " << style << "\n"; 
  } 
}; 
 
int main() { 
  Triangle t1("isosceles", 4.0, 4.0); 
  Triangle t2("right", 8.0, 12.0); 
 
  cout << "Info for t1:\n"; 
  t1.showStyle(); 
  t1.showDim(); 
  cout << "Area is " << t1.area() << "\n"; 
 
  cout << "\n"; 
  cout << "Info for t2:\n"; 
  t2.showStyle(); 
  t2.showDim(); 
  cout << "Area is " << t2.area() << "\n"; 
 
  return 0; 
}


listing 10
// Add a constructor to TwoDShape. 
 
#include <iostream> 
#include <cstring> 
using namespace std; 
 
// A class for two-dimensional objects. 
class TwoDShape { 
  // these are private 
  double width; 
  double height; 
public: 
 
  // Default constructor. 
  TwoDShape() { 
    width = height = 0.0; 
  } 
 
  // Constructor for TwoDShape. 
  TwoDShape(double w, double h) { 
    width = w; 
    height = h; 
  } 
 
  // Construct object with equal width and height. 
  TwoDShape(double x) { 
    width = height = x; 
  } 
 
  void showDim() { 
    cout << "Width and height are " << 
             width << " and " << height << "\n"; 
  } 
 
  // accessor functions 
  double getWidth() { return width; } 
  double getHeight() { return height; } 
  void setWidth(double w) { width = w; } 
  void setHeight(double h) { height = h; } 
}; 
 
// Triangle is derived from TwoDShape. 
class Triangle : public TwoDShape { 
  char style[20]; // now private 
public: 
 
  /* A default constructor. This automatically invokes 
     the default constructor of TwoDShape. */ 
  Triangle() { 
    strcpy(style, "unknown"); 
  } 
 
  // Constructor with three parameters. 
  Triangle(char *str, double w, 
           double h) : TwoDShape(w, h) { 
    strcpy(style, str); 
  } 
   
  // Construct an isosceles triangle. 
  Triangle(double x) : TwoDShape(x) { 
    strcpy(style, "isosceles");  
  } 
 
  double area() { 
    return getWidth() * getHeight() / 2; 
  } 
 
  void showStyle() { 
    cout << "Triangle is " << style << "\n"; 
  } 
}; 
 
int main() { 
  Triangle t1; 
  Triangle t2("right", 8.0, 12.0); 
  Triangle t3(4.0); 
 
  t1 = t2; 
 
  cout << "Info for t1: \n"; 
  t1.showStyle(); 
  t1.showDim(); 
  cout << "Area is " << t1.area() << "\n"; 
 
  cout << "\n"; 
 
  cout << "Info for t2: \n"; 
  t2.showStyle(); 
  t2.showDim(); 
  cout << "Area is " << t2.area() << "\n"; 
 
  cout << "\n"; 
 
  cout << "Info for t3: \n"; 
  t3.showStyle(); 
  t3.showDim(); 
  cout << "Area is " << t3.area() << "\n"; 
 
  cout << "\n"; 
 
  return 0; 
}

listing 11
// Create a subclass of Vehicle called Truck. 
 
#include <iostream> 
using namespace std; 
 
// Declare the Vehicle class. 
class Vehicle {  
  // These are private. 
  int passengers; // number of passengers  
  int fuelcap;    // fuel capacity in gallons 
  int mpg;        // fuel consumption in miles per gallon 
public: 
  // This is a constructor for Vehicle. 
  Vehicle(int p, int f, int m) { 
    passengers = p; 
    fuelcap = f; 
    mpg = m; 
  } 
 
  // Compute and return the range. 
  int range() { return mpg * fuelcap; } 
 
  // Accessor functions. 
  int get_passengers() { return passengers; } 
  int get_fuelcap() { return fuelcap; } 
  int get_mpg() { return mpg; } 
}; 
 
// Use Vehicle to create a Truck specialization.    
class Truck : public Vehicle {  
  int cargocap; // cargo capacity in pounds  
public: 
 
  // This is a constructor for Truck.  
  Truck(int p, int f, 
               int m, int c) : Vehicle(p, f, m)  
  {  
    cargocap = c;  
  }  
 
  // Accessor function for cargocap. 
  int get_cargocap() { return cargocap; } 
};  
    
int main() {    
  
  // construct some trucks 
  Truck semi(2, 200, 7, 44000);    
  Truck pickup(3, 28, 15, 2000);    
  int dist = 252; 
 
  cout << "Semi can carry " << semi.get_cargocap() <<