Medium · System Design

Design Tic-Tac-Toe

Given n and a sequence of valid moves (row, col, player) on an n × n Tic-Tac-Toe board, where player is 1 or 2 and each move takes an empty cell, return for each move the player's number if that move completes a full row, column or diagonal of that player's marks, and 0 otherwise.

Examples

Example 1

{
  "n": 3,
  "moves": [
    {"row": 0, "col": 0, "player": 1},
    {"row": 1, "col": 0, "player": 2},
    {"row": 0, "col": 1, "player": 1},
    {"row": 1, "col": 1, "player": 2},
    {"row": 0, "col": 2, "player": 1}
  ]
}

Output: [0, 0, 0, 0, 1]

Example 2

{
  "n": 3,
  "moves": [
    {"row": 0, "col": 0, "player": 1},
    {"row": 1, "col": 1, "player": 2},
    {"row": 0, "col": 1, "player": 1},
    {"row": 0, "col": 2, "player": 2},
    {"row": 1, "col": 2, "player": 1},
    {"row": 2, "col": 0, "player": 2}
  ]
}

Output: [0, 0, 0, 0, 0, 2]

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