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Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.


This is a league based challenge.

For this challenge, three leagues for the same game are available. Once you have proven your skills against the Boss, you will access a higher league and extra rules will be available.

  The Goal

Win. Don't die.

Shoot at your enemy with bullets and missiles, watch out for their weapons. Be careful - the forcefield, which was used to trap your enemy, seems to also be keeping you inside. Keep away from the edge - crash with the forcefield will destroy your ship!


The game is played on a map 1700 units wide (along x axis) and 1080 units high (along y axis). Point (0,0) is in the upper left corner.

You and your opponent each own one starship, which has 10 health points.

The ship has an infinite number of bullets.

The bullet can be shot every two turns. It detonates automatically in the first tick, when its distance to the closest enemy unit, that was in its damage radius, starts to increase. Ending its lifetime (after 7 turns), or going out of health points (a bullet has its own 10 health points) also detonates the bullet.

Bullet's damage radius is 120, the damage caused at the bullet's position is 10 and decreases linearly with the distance to it, reaching 0 at damage radius. The bullet is shot with the given velocities along each axis (in relation to the ship), with the resultant velocity being clipped to be at most 100.

The ships start at symmetrical positions, close to the center of the board.

Ships move with the given acceleration along each axis, with the resultant acceleration (interpreted as a vector) being clipped to length 10.

Hitting the edge of the board immediately sets the unit's (ship's or bullet's) health to 0, causing it to die/detonate.

Keep in mind that your own weapons are as harmful to you as your opponent's!

Each game turn consists of 5 ticks, so that the units' positions are updated 5 times a turn.

Each turn takes exactly 1 time unit, so that every tick takes 1/5 of a time unit - for example, a ship moving with the speed of 10 will travel 2 units of space every tick, so 10 every turn.

The player whose ship reaches 0 health points first - loses.

The game lasts up to 100 turns. If both players survive that long, it's a draw.

Stats summary:

unit number of damage damage radius health lifetime max acceleration
ship 1 - - 10 - 10
bullet 10 120 10 7 -

Note that there is a debug mode available in the game settings!


This contribution was developed for the Programming Programming Games course, University of Wrocław, 2021.

Authored by Michał Opanowicz (@MichalOp), Katarzyna Miernikiewicz (@Manwi23), Agnieszka Pawicka (@Agn).

Supervised by Jakub Kowalski (@aCat).

  Game Input

Input for one game turn
Line 1: One integer units for the number of units on the board.
Next units lines: Two integers unit_id, faction, being the unit's unique ID and faction (1 for the player, -1 for the opponent), one char type being Ship or Bullet, six floats health, position_x, position_y, velocity_x, velocity_y, gun_cooldown for the unit's health points left, its position on each axis and velocity on each axis, followed by gun cooldown, which indicates the number of turns till the next bullet can be shot if this unit is a ship, -1 otherwise.
Output for one game turn
1 line, a command for your ship in the form: unit_id | A x y | F x y , having one or more commands for the ship separated by |. unit_id is your ship's ID. You can also use S instead of unit_id. x,y are both dot-formatted doubles - if given with more precision than 2 decimal places, then rounded up to at most 2 decimal places.

Available commands:
  • [A | ACCELERATE] ax ay - put acceleration ax on x-axis, ay on y-axis (with instant effect)
  • [F | FIRE] vx vy - fire a bullet with velocity vx on x-axis, vy on y-axis (relative to ship)
  • [P | PRINT] message - print a message - it can also be a multiline one, with lines split with an escaped newline symbol ("\\n")
  • [W | WAIT] - do nothing

Example outputs:

You want to put acceleration (0, -4) on your ship, which has id 23, and at the same time fire a bullet with velocity (relative to the ship) (2, 1).
23 | A 0 -4 | F 2 1

You want to not do anything in this turn.
23 | W

You want to only fire a bullet with velocity (relative to the ship) (1, 1) and print "Hello there" and a debug information (note that 'S' is used instead of unit_id).
S | F 1 1 | P Hello there

What is in the higher league?

Missiles! They have their own engines and can be moved around just as your ship. A deadly weapon.

A higher resolution is required to access the IDE

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