// Textbook fragment 03.30
                                                // draw a tick with no label
public static void drawOneTick(int tickLength) { drawOneTick(tickLength, -1); }
                                                // draw one tick
public static void drawOneTick(int tickLength, int tickLabel) {
  for (int i = 0; i < tickLength; i++)
    System.out.print("-");
  if (tickLabel >= 0) System.out.print(" " + tickLabel);
  System.out.print("\n");
}
public static void drawTicks(int tickLength) {  // draw ticks of given length
  if (tickLength > 0) {                         // stop when length drops to 0
    drawTicks(tickLength-1);                    // recursively draw left ticks
    drawOneTick(tickLength);                    // draw center tick
    drawTicks(tickLength-1);                    // recursively draw right ticks
  }
}
public static void drawRuler(int nInches, int majorLength) {    // draw ruler
  drawOneTick(majorLength, 0);                  // draw tick 0 and its label
  for (int i = 1; i <= nInches; i++) {
    drawTicks(majorLength-1);                   // draw ticks for this inch
    drawOneTick(majorLength, i);                // draw tick i and its label
  }
}