Drop colored disks into a vertical grid. Connect four disks in a line to win.

message State {
  // Required field to indicate the player who should be making the next move
  // Values = 0 or 1
  int32 player_turn_idx = 1;

  /*
  Array of size 42 initialized to -1, representing an empty 6 by 7 board.
  The values of board can be -1, 0, or 1. 
  Placing a piece in index x will set the value of board[x] to the player's index.
  Array is row major order from the bottom up: 
  • index 0 is bottom left
  • index 6 is bottom right
  • index 35 is top left
  • index 41 is top right
  */
  repeated int32 board = 2;
}
