/**
   roomba.cpp
   31-jan-2007/sklar

   this program demonstrates a simple robot (called "roomba")
   wandering around in a simulated room. the robot can move in any of
   four directions (forward, backward, left or right) within a "grid"
   so that any move changes the robot's location by one grid square.
   for example, if the robot starts at location (0,0) and moves forward,
   it will end up at location (0,1).

*/


// section 1: include C++ library definitions
#include <iostream>
using namespace std;


// section 2: declare variables
int x;
int y;


// section 3: declare methods
int display() {
  cout << "the roomba is at location (";
  cout << x;
  cout << ",";
  cout << y;
  cout << ")\n";
  return 0;
} // end of display()


int moveForward() {
  cout << "moving forward...\n";
  y = y + 1;
  return 0;
} // end of moveForward()


int moveBackward() {
  cout << "moving backward...\n";
  y = y - 1;
  return 0;
} // end of moveBackward()


int moveLeft() {
  cout << "moving left...\n";
  x = x - 1;
  return 0;
} // end of moveLeft()


int moveRight() {
  cout << "moving right...\n";
  x = x + 1;
  return 0;
} // end of moveRight()



// section 4: define main method
int main() {
  x = 0;
  y = 1;
  display();
  moveForward();
  moveForward();
  display();
  moveBackward();
  display();
  moveLeft();
  display();
  moveRight();
  display();
} // end of main()