"It is plain indeed that in spite of later estrangement Hobbits are relatives of ours: far
nearer to us than
Elves, or even than Dwarves. Of old they spoke the languages of Men, after their own
fashion, and liked and
disliked much the same things as Men did. But what exactly our relationship is can no longer
"Hobbits are an unobtrusive but very ancient people, more numerous formerly than they are
today; for they love
peace and quiet and good tilled earth: a well-ordered and well-farmed countryside was their
-- "The Lord of the Rings" J.R.R.Tolkien
Two Hobbits are trying to catch a chicken in the yard. It should be an easy task, but these two
neighbours never seem to get along. Now a chicken got loose and they need to catch it, but they
refuse to talk to each other. So, we need to find an algorithm which will work for the both of
the Hobbits independently, allowing either of them to catch a chicken without walking into a
fence, tree or each other. One last thing, Hobbits cannot run or wait forever. After all.
catching the chicken is important, but Hobbits must adhere to their strict dinner schedule.
You are given a yard map as a sequence of strings where:
- "." is an empty cell;
- "I" is managed Hobbit;
- "S" is companion;
- "C" is chicken (our target);
- "X" is obstacle (a tree, a rock etc)
The yard is surrounded by a fence.
The chicken and Hobbits can move in 8 direction into neighbouring cells (including diagonals).
And they can wait and stay in one place for a while.
Actions are described with the following strings:
- "N" north, "S" south, "W" west, "E" east;
- "NW" north-west, "NE" north-east, "SW" south-west, "SE" south-east;
- "" (empty string) is to wait.
The Chicken is unpredictable and can use various tactics (including random movement), but he can
not go out of the yard. Hobbits can not run in obstacles or in fences. And they should not
struck each other, even for the final jump by the chicken.
Now for the tricky part. Your function will be called twice in each step - once for the first
Hobbit and once for the second Hobbit. The Hobbits cannot communicate with each other and make
their moves simultaneously. So be careful with moving both Hobbits into one square. You should
move a Hobbit into the chickens square to win, but only one should make the move as two hobbits
entering the same cell would count as them colliding. The Hobbits and the chicken move
simultaneously, so if you just jump to a cell where is chicken, then is not guaranteed that you
will catch it. Since dinner time is coming soon for the Hobbits, you have no more 100 moves to
catch the chicken.
This is a "multicall" mission and your function will be called until you win or lose. Each cycle
of steps is running in a new environment, so you can use global variables between steps, but for
the new "hunt" they will be reseted..
This map will be looked little different for each function call:
A yard map as a tuple of strings. Your function is called twice for
The action as a string. One of ("N", "S", "W", "E", "NW", "NE", "SW",
"......")) # return an action
How it is used:
This concept is using for automated robots which should work as a team without needing a direct
connection, like factory manufacturing robots or Cylons. These robots and AI should be complex
enough to "think" about and predict the actions of other objects.
3 < len(yard) ≤ 10
all(3 < len(row) ≤ 10 and len(row) == len(yard) for row in yard)