RoboRally 1.0 Solution
The challenge was to get Twonky (that's the little red robot) onto the flag and win the game.
You've been dealt the following 9 cards:
Move 3, Move 2, Move 1, Move 1, Turn Left, Turn Right, U-Turn, Backup, Backup.
There were no less than 4(!) solutions to the above problem. The one that I had intended when making up the puzzle was:
Move 3, Move 2, Backup, U-Turn, Backup
I still think this is the "prettiest" solution but of course, I'm biased. There were a couple of variations on this move:
Move 3, Move 1, Turn Right, Backup, Backup (This was by far the most popular solution.)
Move 3, Move 2, U Turn, Move 1, Move 1
The surprising solution was:
Turn Left, Move 2, U-Turn, Backup, Move 3
I had tried plenty of variations to make the southern route appear to be solvable without actually being so. This is the real trick to these designs, you want to have a couple of red herrings to throw people off the track. If you make it too restrictive it becomes obvious that its not possible that way. I suppose I'll need to do some blind-testing of these in the future.
An honorary mention must go to Phil Fleischman who wrote:
Move 3, Move 1, Turn Right, Backup, Backup
This assumes no other robot is about to come onto the board and push Twonky
or shoot him with a Tractor Beam, Pressor Beam, Mini-Howitzer, Scrambler, or
If Twonky has Crab Legs, he can get there in only four phases by Move 2, Move 3, Move 1 & Turn Right, Move 1.
If Twonky has Fourth Gear, he can get there in only four phases by eliminating the Move 1.
If Twonky has Overload Override, he can get there in four phases by combining the Move 3 and Move 1; or by Move 2, Move 3 & Turn Right, Move 1 & Turn Left, Move 1; or in three phases by Turn Left, Move 3 & U-Turn, Move 2 & Move 1.
If Twonky has Retro-Rockets, he can get there in only three phases by Turn Right, (fire) Backup, Move 3.
If Twonky has Reverse Gear, he can get there in only four phases by Turn Left, Move 3, Backup (2), Backup.
Twonky cannot get to the flag in fewer than five phases with Big Jet,
Brakes, Dual Processor, Frog Legs, Gyroscopic Stabilizer, or Robo-Copter.
This assumes he has only one of these options. With more than one of the
above-mentioned options, it may be possible to get there in fewer phases.
You clearly have too much time on your hands Phil! Nice job though.
- Greg Aleknevicus