Introduction to Computer Science

Methods for you to implement:

applyStarbucksTruckAction(Racer racer) – O(N²) Strategy

• Goal: Charge for N actions, then move 1 step. Repeat.
• Charge Time: N (Same as track length).
• Action Logic:
  • Check if the battery is full using getBattery() and getChargeTime().
  • If full: Move the racer forward by 1 step.
  • If not full: Charge the battery.

Testing:

applyNLogNExpressAction(Racer racer) – O(N log N) Strategy

• • Goal: Charge for N actions, then teleport distances of 1, 2, 4, 8, … (powers of 2). Repeat.
  • Charge Time: N (Same as track length).
  • Action Logic:
    • Check if the battery is full using getBattery() and getChargeTime().
    • If not full: Charge the battery.
    • If full: Calculate the appropriate distance to move based on how many jumps have already been completed.
    • UPDATED 4/21 5PM: To find the next jump look at the total distance a racer has already covered. We want to know roughly “2 raised to what power k is close to the total distance traveled so far?”.
      • In Java, Math.log(x) calculates the natural logarithm (base e). To get base-2 we use the standard math formula log_2(x) = log(x) / log(2). 
      • Calculating (int) (Math.log(racerDistance) / Math.log(2)) represents the exponent of the last power-of-2 jump completed. The (int) part just drops any decimal, giving us the whole number.
    • Make sure the racer doesn’t move beyond the track length.
    • Move the racer by the determined distance.

Handle the case where the racer hasn’t moved yet separately (first jump should be distance 1).

Always ensure the racer moves at least 1 step when teleporting if it hasn’t finished the race yet.

Testing:

applyLogNExpressAction(Racer racer) – O(log N) Strategy

• • Goal: Teleport distances of 1, 2, 4, 8, … (powers of 2) with no charging.
  • Charge Time: 0 (No charging needed).
  • Action Logic:
    • Calculate the appropriate distance to move for this action, which should be a power of 2 based on which action it is. 
    • Make sure the racer doesn’t move beyond the track length by comparing the calculated distance with the remaining distance.
    • Move the racer by the determined distance.

Always ensure the racer moves at least 1 step if it hasn’t finished the race yet.

applyActionStrategy(Racer racer)

• This method determines which strategy to apply based on the racer’s name.
• Use a conditional structure (switch or if-else) to call the appropriate strategy method for each racer type.
• The racer names are: “ScarletKnight”, “StarbucksTruck”, “LogNExpress”, and “NLogNExpress”.

Testing: *this will test a combination of all the previous methods. Here are more examples

rankRacers(ArrayList racers)

• This static method sorts the provided list of racers based on their performance.
• Ranking Criteria:
  1. Primary: Greatest distance traveled (getDistance())– Racers that traveled farther should be ranked higher
  2. Secondary (Tie-breaker): Fewest actions taken (getActionsCounts())– Racers with fewer actions should be ranked higher. *updated 4/22 @2pm
• You can implement this using any basic sorting algorithm (insertion sort). One approach is to iterate through the list and reorder it based on the criteria above.
• You may want to the following Java:
  • racers.get(index) // gets the object at the specified index of the list
  • racers.set(index, object) // sets the object at the specified index of the list

Testing: (updated 4/24)

simulateRace(long cutoff)

• This method contains the main simulation loop.
• Keep track of how many actions have been simulated.
• In each iteration of the main loop:
  • Check if all racers have finished or if the maximum action count (cutoff) has been reached.
  • For each racer that hasn’t finished, apply its action strategy using applyActionStrategy.
  • Keep track of whether all racers have finished to know when to stop the simulation.
• After the simulation is complete, rank the racers using rankRacers and return the result.

Testing:

* To watch a video of the full simulation click *here*
You can see the racers move according to their runtime which is really cool!!!

Executing and Debugging

• You can run your program through VSCode or you can use the Terminal to compile and execute. We suggest running through VSCode because it will give you the option to debug.
• Test each method as you go with the directions under each method
• How to debug your code. You will have to create a launch.json file and configure it correctly (Run -> Add Configuration).
• If you choose the Terminal:

  If you prefer to compile and run the project from the command line:

  1. Navigate to the Project Root: Open your terminal or command prompt and change the directory to the root folder of theRURacingproject (the folder containing the source files and input files).
     
     cd path/to/RURacing
  2. Compile: Use thejavaccommand.
     

     # Compile 
     javac *.java -encoding UTF-8

     Ensure you have a Java Development Kit (JDK) 

  3. Run: Use the javacommand. 
     

     # Run
     java Driver

• If you choose the Driver:
  • Click the play button in the top right corner when you’re on the Driver file