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Learning Opportunities

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


  The Goal

The goal of the game is to create a chain of volcanoes that connects a tile in the northern hemisphere to it's corresponding tile in the southern hemisphere.

Opposing tiles are conveniently numbered so that N16 (north 16) is opposite S16 (south 16).

Since the board is a 2D representation of a Pentakis Icosidodecahedron (an 80-faced sphere-ish shape), tiles connect around the edges of the board (e.g., N40 connects to N21 and S17 connects to S18).


On your turn you may perform one of the following actions.

  1. Place a new level 1 volcano of your color on any empty tile.
  2. Increase the level of one of your existing volcanoes by one (up to a maximum level of 4).

Play progresses as follows.

  1. Blue's turn
  2. Orange's turn
  3. Growth (every volcano on the board gains one level)
  4. Orange's turn
  5. Blue's turn
  6. Growth

This cycle repeats until a player wins by successfully creating an unbroken chain of volcanoes from one side of the board to the other.

When a volcano advances to level 4 (during a player's turn or a growth turn), it erupts with the following effects.

  • The level 4 volcano becomes dormant (it stops growing)
  • Adjacent empty tiles become level 1 volcanoes for the team who owns the erupting volcano.
  • Adjacent volcanoes on the same team as the erupting volcano are increased by one level.
  • Adjacent volcanoes on the opposite team as the erupting volcano are destroyed and leave behind empty tiles.
Victory Conditions
Win by connecting any northern tile to its corresponding southern tile with an unbroken chain of volcanoes.

  Expert Rules

Since the connections between tiles are tedious to set up, they are provided to you in the initialization inputs.

Eruptions can trigger further eruptions. If an infinite chain of eruptions is detected then the game is considered a draw.

It is possible for both players to complete a path at the same time during the growth phase. If this happens then the game is declared a draw.

Game concept by Simon Dorfman.

Code is available on GitHub.

  Game Input

Input (first move only)

Line 1: numberOfTiles, the total number of tiles on the board

Next numberOfTiles lines: 4 space-separated values:

  • tileName, the name of the tile at the given index
  • neighbor1, the index of a neighboring tile
  • neighbor2, the index of a neighboring tile
  • neighbor3, the index of a neighboring tile
Input (each turn)

Line 1: currentPosition, a space-separated list of the volcano levels of all numberOfTiles tiles on the board, with positive values for your volcanoes and negative values for your opponent's volcanoes

Line 2: validMoves, a space-separated list of valid moves in the current position


Line 1: move, the name of the tile to play on or RANDOM to play a random move

numberOfTiles = 80

Bots must respond within 100 milliseconds.

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