Knight Probability in Chessboard LeetCode solution in JavaScript

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var knightProbability = function (n, k, row, column) {
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  if (k === 0) return 1;
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  const dirs = [
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    [-2, -1],
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    [-1, -2],
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    [1, -2],
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    [2, -1],
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    [2, 1],
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    [1, 2],
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    [-1, 2],
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    [-2, 1],
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  ];
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  const dp = Array(k + 1)
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    .fill("")
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    .map((_) =>
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      Array(n)
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        .fill("")
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        .map((_) => Array(n).fill(0))
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    );
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  const isOut = (pos) => pos < 0 || pos > n - 1;
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  const move = (x = row, y = column, step = k) => {
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    if (step === 0) return 1;
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    const moves = dp[step][x][y];
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    if (moves !== 0) return moves;
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    for (const [mvoeX, moveY] of dirs) {
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      const nextX = x + mvoeX;
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      const nextY = y + moveY;
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      if (isOut(nextX) || isOut(nextY)) continue;
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      dp[step][x][y] += move(nextX, nextY, step - 1);
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    }
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    return dp[step][x][y];
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  };
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  move();
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  return dp[k][row][column] / 8 ** k;
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};