// Learning Processing
  // Daniel Shiffman
  // http://www.learningprocessing.com
  
  // Example 6-5: Another infinite loop. Don't do this!
  
  int y = 80;        // Vertical location of each line
  int x = 0;         // Horizontal location of first line
  int spacing = 10;  // How far apart is each line
  int len = 20;      // Length of each line
  int endLegs = 150; // Where should the lines stop?
  
  void setup() {
    size(200,200);
  }
  
  void draw() {
    background(0);
    stroke(255);
    x = 0;
    
    // The spacing variable, which sets the distance in between each line, is assigned a value equal to mouseX divided by two.
    // THIS LINE IS COMMENTED OUT SO THAT THE SKETCH DOES NOT CRASH
    // IF YOU PUT IT BACK IN THIS SKETCH WILL CRASH!
    // spacing = mouseX / 2; 
    
    // Exit Condition: when x is greater than endlegs.
    while (x <= endLegs) { 
      line(x,y,x,y + len);
      // Incrementation of x. 
      // x always increases by the value of spacing.
      //  What is the range of possible values for spacing?
      x = x + spacing; 
    }
  }