Coding Arena — Boost your coding skill and win cool prizes — Panaxeo — Crazy good software teams

Competition •

Code a bot. Sink ships. Win prizes.

Timer runs out on December 15.

tl;dr:

Your task is to code the most efficient Battleships bot in whatever language you love. Explore the rules.
You solve various maps over an API.
The player whose bot achieved the best score before 23:59:59, Dec 15, ‘23 wins cool prizes.
There are three categories with one winner in each. Login to play.
Join us on Discord and chat with fellow contestants.
Still not sure? Read our FAQs.

Welcome to the Coding Arena

The Coding Arena is a Panaxeo tradition. Every year, we measure our egos coding skills. For the second time in forever, it’s open to the public! Y’all are very welcome to enter!

This year is all about Battleships. Your goal is to win 200 matches and destroy all enemy ships by firing at coordinates in a square grid. Unfamiliar with the basic rules of this game? Read on.

Login below, get your API token and start playing Battleships with us.

How to play?

Sink all ships to finish a map. There are 200 maps in a single game. Your bot can play up to 20 games overall.

The bot starts a map by firing at coordinates. The map is a 12x12 grid. There are 6 ships to sink. Once you sink them all, the map ends.

Your goal is to use the least amount of turns to finish all maps in a game. This is your score. The lower your score, the higher you rise in the leaderboard.

Explore the API ↓

**The fleet to sink:**Avengers Helicarrier (9 spaces), Carrier (5 spaces), Battleship (4), Destroyer (3), Submarine (3), and Patrol Boat (2).

There’s a special twist, though!

An Avengers Helicarrier™ has been stolen! (Along with those other ships.) By destroying it, you’ll release the captured Avengers. One of them can help you with their unique abilities.
Thor can reveal 11 spaces at once with his lightning. The one you’re firing at + 10 random spaces. All in a single turn.
Hulk can sink a whole ship at once. If you fire at a space with an actual ship and ask Hulk for help, he’ll destroy the entire ship.
Iron Man will use his scanners to reveal the smallest undiscovered ship.
You can use an Avenger ability in the next turn immediately after destroying the Helicarrier. Only one Avenger is available per match, only once.

Explore the API calls to learn more.

Map rules

Ships can only be placed vertically or horizontally.
Diagonal placement is not allowed.
No part of a ship may hang off the edge of the map.
Ships may not overlap each other.
No ship can touch another ship, not even diagonally.
Once the guessing begins, the players may not move the ships.

The Battleship API

Endpoints

Getting the status of an ongoing game 📋

GET /fire

Path parameters

None

Query parameters

name allowed value required description

test yes false Query will be performed on test data for simulation, no change to real game data, user score / number of tries etc.

name type data type description

Authorization Bearer token string Authorization token copied from the UI

Responses

http code content-type response

200 application/json; charset=utf-8 FireResponse

400 application/json; charset=utf-8 {"error": "Max tries already reached"}

400 application/json; charset=utf-8 {"error": "Invalid query parameter or query parameter value supplied"}

403 application/json; charset=utf-8 {"error": "Unauthorized"}

Example cURL

 curl --request GET --url https://europe-west1-ca-2023-dev.cloudfunctions.net/battleshipsApi/fire --header 'Authorization: Bearer $token'

Firing at specified position 🎯

GET /fire/**:row**/**:column**

Path parameters

name data type required description

row integer true vertical position on the board from range [0,11]

column integer true horizontal position on the board from range [0,11]

Query parameters

name allowed value required description

test yes false Query will be performed on test data for simulation, no change to real game data, user score / number of tries etc.

name type data type description

Authorization Bearer token string Authorization token copied from the UI

Responses

http code content-type response

200 application/json; charset=utf-8 FireResponse

400 application/json; charset=utf-8 {"error": "Max tries already reached"}

400 application/json; charset=utf-8 {"error": "Invalid values for row or column"}

400 application/json; charset=utf-8 {"error": "Invalid query parameter or query parameter value supplied"}

403 application/json; charset=utf-8 {"error": "Unauthorized"}

Example cURL

 curl --request GET --url https://europe-west1-ca-2023-dev.cloudfunctions.net/battleshipsApi/fire/:row/:column --header 'Authorization: Bearer $token'

Firing at specified position with help of avenger 🦸‍♂

GET /fire/**:row**/**:column**/avenger/**:avenger**

Path parameters

name data type required description

row integer true vertical position on the board from range [0,11]

column integer true horizontal position on the board from range [0,11]

avenger string true use the power of specified avenger (hulk, ironman or thor)

Avenger abilities explained

thor ability will hit 10 random map points at maximum (at maximum = if there are fewer untouched map points available than 10, all of them will be targeted by this ability)
ironman ability will return 1 map point of the smallest non-destroyed ship, this map point will be unaffected (the purpose of this ability is to give a hint to the user)
hulk ability will destroy the whole ship if the map point specified by the row/column combination at the api endpoint hits the ship (all the map points belonging to this ship will be marked as destroyed)

Query parameters

name allowed value required description

test yes false Query will be performed on test data for simulation, no change to real game data, user score / number of tries etc.

name type data type description

Authorization Bearer token string Authorization token copied from the UI

Responses

http code content-type response

200 application/json; charset=utf-8 AvengerFireResponse

400 application/json; charset=utf-8 {"error": "Max tries already reached"}

400 application/json; charset=utf-8 {"error": "Invalid values for row or column"}

400 application/json; charset=utf-8 {"error": "Invalid value for avenger"}

400 application/json; charset=utf-8 {"error": "Avenger unavailable"}

400 application/json; charset=utf-8 {"error": "Invalid query parameter or query parameter value supplied"}

403 application/json; charset=utf-8 {"error": "Unauthorized"}

Example cURL

 curl --request GET --url https://europe-west1-ca-2023-dev.cloudfunctions.net/battleshipsApi/fire/:row/:column/avenger/:avenger --header 'Authorization: Bearer $token'

Reset ongoing game ↻

Calling this endpoint results in resetting the ongoing game, but your attempt will be counted as one full game without saving the score.

GET /reset

Path parameters

None

Query parameters

name allowed value required description

test yes false Query will be performed on test data for simulation, no change to real game data, user score / number of tries etc.

name type data type description

Authorization Bearer token string Authorization token copied from the UI

Responses

http code content-type response

200 application/json; charset=utf-8 {"availableTries": number }

400 application/json; charset=utf-8 {"error": "Max tries already reached"}

400 application/json; charset=utf-8 {"error": "No ongoing game found"}

400 application/json; charset=utf-8 {"error": "Invalid query parameter or query parameter value supplied"}

403 application/json; charset=utf-8 {"error": "Unauthorized"}

Example cURL

 curl --request GET --url https://europe-west1-ca-2023-dev.cloudfunctions.net/battleshipsApi/reset --header 'Authorization: Bearer $token'

Response models

FireResponse

Model details

name data type description

grid string 144 chars (12x12 grid) representing updated state of map, '*' is unknown, 'X' is ship, '.' is water.

cell string Result after firing at given position ('.' or 'X'). This field may be empty ('') if player calls /fire endpoint or tries to fire at already revealed position.

result boolean Denotes if fire action was valid. E.g. if player calls /fire endpoint or fire at already revealed position, this field will be false.

avengerAvailable boolean Avenger availability after the player's move.

mapId integer ID of the map, on which was called last player's move. This value will change when player beats current map.

mapCount integer Fixed number of maps which are required to complete before completing one full game.

moveCount integer Number of valid moves which were made on the current map. Invalid moves such as firing at the same position multiple times are not included.

finished boolean Denotes if player successfully finished currently ongoing game => if player completed mapCount maps. Valid move after getting true in this field results in new game (or error if player has already achieved max number of tries).

Example

{
    "grid": "*...**********************XX.**********************************.***********.***********.***********************************************.********",
    "cell": "X",
    "result": true,
    "avengerAvailable": false,
    "mapId": 0,
    "mapCount": 2,
    "moveCount": 10,
    "finished": false
}

AvengerFireResponse

Model details

AvengerFireResponse includes all the fields from FireResponse and adds the following

name data type description

avengerResult {mapPoint: {x: integer, y: integer }, hit: boolean}[] mapPoint's values x (row) and y (column) denote coordinates which were affected by avenger ability. Value of hit denotes, if coordinates specified by mapPoint have hit a ship.

Example

{
    "grid": "*...**********************XX.****..****************************.***********.***********.***********************************************.********",
    "cell": ".",
    "result": true,
    "avengerAvailable": false,
    "mapId": 0,
    "mapCount": 2,
    "moveCount": 12,
    "finished": false,
    "avengerResult": [
        {
            "mapPoint": {
                "x": 9,
                "y": 2
            },
            "hit": false
        }
    ]
}

**Frequently asked

questions**

We want a level playing field for students and juniors. that’s why there are categories – juniors and seniors. There will be a winner in each of these categories.

Not sure which one to choose from? Here’s a rule of thumb:

– With less than 2 years of professional coding experience, pick the junior category.

– With more than 2 years of coding experience, pick the senior category.
The test API is for functionality and communication tests. It simulates a real game but the number of requests is limited to 200 per day.

It's there for you to try the API without committing to a real game.
Coding arena started out as a Panaxeans-only competition, so it’s a matter of legacy. Plus, only Panaxeans can win eternal glory in the Hall of Fame. Wanna become a Panaxean?
You can enter the Coding Arena at any point up to 15 December 2023. Time of entry doesn’t matter; your score does.

http code	content-type	response
`200`	`application/json; charset=utf-8`	FireResponse
`400`	`application/json; charset=utf-8`	`{"error": "Max tries already reached"}`
`400`	`application/json; charset=utf-8`	`{"error": "Invalid query parameter or query parameter value supplied"}`
`403`	`application/json; charset=utf-8`	`{"error": "Unauthorized"}`

name	data type	required	description
row	integer	true	vertical position on the board from range [0,11]
column	integer	true	horizontal position on the board from range [0,11]

http code	content-type	response
`200`	`application/json; charset=utf-8`	`{"availableTries": number }`
`400`	`application/json; charset=utf-8`	`{"error": "Max tries already reached"}`
`400`	`application/json; charset=utf-8`	`{"error": "No ongoing game found"}`
`400`	`application/json; charset=utf-8`	`{"error": "Invalid query parameter or query parameter value supplied"}`
`403`	`application/json; charset=utf-8`	`{"error": "Unauthorized"}`

name	data type	description
grid	string	144 chars (12x12 grid) representing updated state of map, '*' is unknown, 'X' is ship, '.' is water.
cell	string	Result after firing at given position ('.' or 'X'). This field may be empty ('') if player calls /fire endpoint or tries to fire at already revealed position.
result	boolean	Denotes if fire action was valid. E.g. if player calls /fire endpoint or fire at already revealed position, this field will be false.
avengerAvailable	boolean	Avenger availability after the player's move.
mapId	integer	ID of the map, on which was called last player's move. This value will change when player beats current map.
mapCount	integer	Fixed number of maps which are required to complete before completing one full game.
moveCount	integer	Number of valid moves which were made on the current map. Invalid moves such as firing at the same position multiple times are not included.
finished	boolean	Denotes if player successfully finished currently ongoing game => if player completed mapCount maps. Valid move after getting true in this field results in new game (or error if player has already achieved max number of tries).

Files

GAME_ASSIGNMENT.md

Latest commit

History

GAME_ASSIGNMENT.md

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Coding Arena — Boost your coding skill and win cool prizes — Panaxeo — Crazy good software teams

Competition •

Code a bot. Sink ships. Win prizes.

tl;dr:

Welcome to the Coding Arena

How to play?

There’s a special twist, though!

Map rules

The Battleship API

Endpoints

Getting the status of an ongoing game 📋

Path parameters

Query parameters

Responses

Example cURL

Firing at specified position 🎯

Path parameters

Query parameters

Responses

Example cURL

Firing at specified position with help of avenger 🦸‍♂

Path parameters

Avenger abilities explained

Query parameters

Responses

Example cURL

Reset ongoing game ↻

Path parameters

Query parameters

Responses

Example cURL

Response models

FireResponse

Example

AvengerFireResponse

Example

**Frequently asked