Tic-tac-toe is played by two players A and B on a 3 x 3 grid.
Here are the rules of Tic-Tac-Toe:
Players take turns placing characters into empty squares (" ").
The first player A always places "X" characters, while the second player B always places "O" characters.
"X" and "O" characters are always placed into empty squares, never on filled ones.
The game ends when there are 3 of the same (non-empty) character filling any row, column, or diagonal.
The game also ends if all squares are non-empty.
No more moves can be played if the game is over.
Given an array moves where each element is another array of size 2 corresponding to the row and column of the grid where they mark their respective character in the order in which A and B play.
Return the winner of the game if it exists (A or B), in case the game ends in a draw return "Draw", if there are still movements to play return "Pending".
You can assume that moves is valid (It follows the rules of Tic-Tac-Toe), the grid is initially empty and A will play first.
Input: moves = [[0,0],[2,0],[1,1],[2,1],[2,2]]
Output: "A"
Explanation: "A" wins, he always plays first.
[X][ ][ ]
[ ][ ][ ]
[ ][ ][ ]
[X][ ][ ]
[ ][ ][ ]
[O][ ][ ]
[X][ ][ ]
[ ][X][ ]
[O][ ][ ]
[X][ ][ ]
[ ][X][ ]
[O][O][ ]
[X][ ][ ]
[ ][X][ ]
[O][O][X]
Input: moves = [[0,0],[1,1],[0,1],[0,2],[1,0],[2,0]]
Output: "B"
Explanation: "B" wins.
[X][X][O]
[X][O][ ]
[O][ ][ ]
Input: moves = [[0,0],[1,1],[2,0],[1,0],[1,2],[2,1],[0,1],[0,2],[2,2]]
Output: "Draw"
Explanation: The game ends in a draw since there are no moves to make.
[X][X][O]
[O][O][X]
[X][O][X]
Input: moves = [[0,0],[1,1]]
Output: "Pending"
Explanation: The game has not finished yet.
[X][ ][ ]
[ ][O][ ]
[ ][ ][ ]
1 <= moves.length <= 9
moves[i].length == 2
0 <= moves[i][j] <= 2
There are no repeated elements on moves.
moves follow the rules of tic tac toe.
Ruby > 2.0
From the solutions/ruby folder with
bundle install
# run the tests with
ruby -I lib:test tic_tac_test.rb --verbose