Ricochet Robots. Game 1, Round 2

Posted by Don B on 13 April, 2020 14 comments

Ricochet Robot: Board Position Turn 2

Standings for round 2

Gavin: 1 token
Everyone else: 0 tokens.

NOTE. You must observe the rule about having at least one bounce. To clarify: all solutions must have at least three moves with no trivial retracing of robot paths. 

If you want to know how this game works see the original blog post here.

Of course I overlooked some logistical issues with running this. To make it a little easier for me and everyone else, I'm making some changes from this round onward to the way we handle solutions - the changed submission process is:

  • At 5:30pm, I will accept and publish all submitted numbers made through the comments section of the blog post for the daily puzzle (the time you submit a number is recorded to resolve ties).
  • After that, everyone then has 15 minutes to submit changes to their numbers if they wish. 
  • All new numbers will be published at 5:45pm, when I will call on the player with the lowest number to submit a solution.
  • If two players submit the same number then the player with the least number of tokens will go first. If there is still a tie then the player among the still tied players who submitted their number first will go first.
  • The nominated player will have 15 minutes to submit their solution.
  • Players can pre-submit solutions at any time if they choose (as a separate comment), but I will not release their solution until 15 minutes after they are called. They can submit a new solution at any point up to that time and I will publish their last submitted solution.
  • If they have not submitted a solution after 15 minutes, I will call on the next player.
  • If their submitted solution fails I will call on the next player. 
  • Repeat this until we either find a winning solution or all submitted numbers are exhausted.
  • If a called player's solution is correct, they win the token.
  • If there is no winning solution the token goes back into the pool.
  • The new state of the board with a new token will be published at 7pm. 


David's solution for round 2: in 4 moves.


← Previous post   |   Next post →

Leave a comment


  1. Don April 14, 2020

    Davids solution wins the token for round 2. I’ll post the new board position at 7pm.

  2. Don April 14, 2020

    I have not received a solution from Alison at this point so, David, you’re up. In 15 minutes I will publish your last submitted solution.

  3. Don April 14, 2020

    Alison – You’re up. You have 15 minutes to submit your solution.

  4. Don April 14, 2020

    You have until 5:45pm to update your numbers.

  5. Don April 14, 2020

    Current leader is Alison. Time order is from bottom to top.

  6. Gavin April 14, 2020


  7. Charlotte April 14, 2020


  8. Don Bone April 14, 2020

    At 5:30pm, I will publish everyone’s lowest number. For today I will delete any “1” numbers (not legal -see the rules) so if you submitted a “1” you can submit another number and it will be accepted. At 5:45, I will publish any new numbers that are lower than the player’s previous number and I will call on the player who is first in priority to submit their solution (see the notes in the original post). You can submit your solution earlier and you can update it. I will publish your last submitted solution at 5:45 and declare whether it has won the token. If it has not then I’ll call on the next player in priority who will have 15 minutes to submit their solution. And so on until we find a winner.

  9. Claire April 14, 2020


  10. Amie April 14, 2020


  11. Don April 14, 2020

    In this version of the game (as interpreted by me) your solution cannot involve directly moving the primary robot (green in this case) to the solution, it must bounce at least once. I extend this to require that the primary robot does not trivially retrace it’s path.

  12. Dave April 14, 2020

    Green: Up, Left, Down, Right

  13. Dave April 14, 2020


  14. Alison April 14, 2020

    Four :)