5 in a Row/Renju

Description:

What you need to play

Renju is played on a grid of black lines (usually 19×19) which is a classic Go grid. Game pieces, called stones, are played on the lines' intersections.

Aim:
 * Black: to get exactly 5 pieces in a row, without making any forbidden moves
 * White: to get 5 or more pieces in a row, or to force Black to make a forbidden move

Rules: players alternate turns, players may not make more than one move in one turn, players may skip their move during their turn.

Gameplay:

Opening sequence:
 * 1) The Black player plays the first three moves. They do this by placing the first black piece, then they (still the black player) place the first white piece, then the second black piece.
 * 2) The current White player then is permitted to choose to become the new Black player, if he or she finds the opening situation particularly disadvantageous for White. (Note: This ensures the original Black player does not intentionally play a poor first move for White.)
 * 3) The new White player (and the White player for the rest of the game) places the second white piece on the board.
 * 4) The new Black player (and the Black player for the rest of the game) places two black pieces on the board. White is essentially given a choice between two potential black moves. White chooses which of the two moves the Black player may make, and the rejected potential move is removed from the board.
 * 5) White plays his or her next move, and the game continues as in the rules above.
 * 1) The new Black player (and the Black player for the rest of the game) places two black pieces on the board. White is essentially given a choice between two potential black moves. White chooses which of the two moves the Black player may make, and the rejected potential move is removed from the board.
 * 2) White plays his or her next move, and the game continues as in the rules above.
 * 1) White plays his or her next move, and the game continues as in the rules above.
 * 1) White plays his or her next move, and the game continues as in the rules above.