Valid Sudoku - LeetCode

Determine if a 9 x 9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:

1. Each row must contain the digits 1-9 without repetition.
2. Each column must contain the digits 1-9 without repetition.
3. Each of the nine 3 x 3 sub-boxes of the grid must contain the digits 1-9 without repetition.

Note:

• A Sudoku board (partially filled) could be valid but is not necessarily solvable.
• Only the filled cells need to be validated according to the mentioned rules.

function solution(board: string[][]) {

  for (let i = 0; i < 9; i ++) {
    for (let j = 0; j < 9; j ++) {
      if (board[i][j] === '.') continue;

      for (let right = j + 1; right < 9; right ++) {
        if (board[i][j] === board[i][right]) {
          return false;
        }
      }

      for (let bottom = i + 1; bottom < 9; bottom ++) {
        if (board[i][j] === board[bottom][j]) {
          return false;
        }
      }

      // 같은 칸에 있는지 확인
    }
  }

  return true;
}

같은 칸에 있는지 체크 못했음..