Lab 6 (On triangles and circles)

You are asked to create a commandline-based interactive program that allows users to add two types of shapes: triangles and circles. The program also allows the user the print the list of stored shapes. Furthermore, it allows the user to modify the stored shapes.

Sample run of this program

./shapes
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: a
== You selected a triangle. ==
Enter position: 0 0
Enter width and height: 1 2
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: b
== You selected a circle. ==
Enter position: 10 2
Enter radius: 1
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: a
== You selected a triangle. ==
Enter position: 3 4
Enter width and height: 1 22
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: p
[0] Triangle
    location: (0, 0)
    width and height: (1, 2)
[1] Radius
    location: (10, 2)
    radius: (1)
[2] Triangle
    location: (3, 4)
    width and height: (1, 22)
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: 1
Enter position: 11 3
Enter radius: 1000
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: p
[0] Triangle
    location: (0, 0)
    width and height: (1, 2)
[1] Radius
    location: (11, 3)
    radius: (1000)
[2] Triangle
    location: (3, 4)
    width and height: (1, 22)
Choose a shape to add
    (a) for triangle
    (b) for circle
    (p) to print the shapes
    (0-9) to modify a shape
    (q) to exit
: q

Some specifics

Source Code

main

#include <iostream>
using namespace std;

class Point
{
  public:
  int x, y;

  Point() {}
  Point(int x, int y) { this->x = x; this->y = y; }
  
  friend ostream& operator<<(ostream& os, const Point& pt) {
    os << "(" << pt.x << ", " << pt.y << ")";
    return os;
  }
};

class Shape
{
  // FEEL FREE TO CHANGE THE THIS CLASS
  // AS LONG AS YOU DON'T HAVE TO CHANGE THE
  // CONTENTS OF MAIN() AND 
  // PRINT_SHAPES() FUNCTIONS

  protected:
  Point _location;

  public:
  Shape() {}
  Shape(const Point& location) : _location(location) {}
  ~Shape() {}
  
  void draw() {
    cout << "location: " << _location << endl;
  }
  
  void get_info_from_user() {
    cout << "Enter position: ";
    cin >> _location.x >> _location.y;
  }
};

// YOU NEED TO COMPLETE THIS CLASS
class Tri
{
  protected:
  int _width, _height;

  public:
  // TODO ...
};

// YOU NEED TO COMPLETE THIS CLASS
class Cir
{
  protected:
  int _radius;

  public:
  // TODO ...
};

/////////////////////////////////////////////////
//
// DO NOT CHANGE CODE BELOW THIS LINE
//
/////////////////////////////////////////////////
#define MAX_SHAPES 10

void print_shapes(Shape** shapes, int n)
{
  for (int i=0; i<n; ++i) {
    cout << "[" << i << "] "; shapes[i]->draw();
  }
}

int main()
{
  Shape* shapes[MAX_SHAPES];

  int n = 0;
  char shape_choice;
  do {
    cout << "Choose a shape to add" << endl;
    cout << "\t(a) for triangle" << endl;
    cout << "\t(b) for circle" << endl;
    cout << "\t(p) to print the shapes" << endl;
    cout << "\t(0-9) to modify a shape" << endl;
    cout << "\t(q) to exit" << endl;
    cout << ": ";
    cin >> shape_choice;

    if (shape_choice == 'q') break;
    
    switch(shape_choice)
    {
      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
        shapes[((int) shape_choice) - 48]->get_info_from_user();
      break;
      case 'a':
        if (n >=  MAX_SHAPES) {
          cout << "== Cannot add any more shapes ==" << endl;
          continue;
        }      
        cout << "== You selected a triangle. ==" << endl;
        shapes[n] = new Tri();
        shapes[n]->get_info_from_user();
        ++n;
      break;
      case 'b':
        if (n >=  MAX_SHAPES) {
          cout << "== Cannot add any more shapes ==" << endl;
          continue;
        }
        cout << "== You selected a circle. ==" << endl;
        shapes[n] = new Cir();
        shapes[n]->get_info_from_user();
        ++n;     
      break;
      case 'p':
        print_shapes(shapes, n);
      break;
      case 'q':
      break;
      default:
        cerr << "== Invalid choice ==" << endl;
      break;
    }
  } while (true);

  for (int i=0; i<n; ++i) delete shapes[i];
}

Learning objectives

Submission

Please submit main.cpp via Canvas. Please put all of your code in the main.cpp file.

Goal

Sample run of this program

Some specifics

Source Code

main

Learning objectives

Submission