As Far from Land as Possible LeetCode solution in JavaScript

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/**
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 * @param {number[][]} grid
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 * @return {number}
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 */
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const DIR = [
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  [0, 1],
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  [0, -1],
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  [1, 0],
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  [-1, 0],
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];
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var maxDistance = function (grid) {
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  const ROWS = grid.length;
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  const COLS = grid[0].length;
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  const cost = new Array(ROWS).fill().map(() => new Array(COLS).fill(Infinity));
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  const que = [];
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  for (let row = 0; row < ROWS; row++) {
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    for (let col = 0; col < COLS; col++) {
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      if (grid[row][col] === 1) {
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        que.push([row, col]);
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        cost[row][col] = 0;
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      }
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    }
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  }
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  if (que.length == 0 || que.length == ROWS * COLS) return -1;
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  while (que.length) {
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    const [row, col] = que.shift();
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    for (const dir of DIR) {
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      const newRow = row + dir[0];
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      const newCol = col + dir[1];
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      if (newRow < 0 || newCol < 0 || newRow >= ROWS || newCol >= COLS)
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        continue;
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      if (cost[newRow][newCol] > cost[row][col] + 1) {
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        cost[newRow][newCol] = cost[row][col] + 1;
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        que.push([newRow, newCol]);
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      }
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    }
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  }
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  let max = 0;
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  for (const row of cost) {
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    max = Math.max(max, ...row);
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  }
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  return max;
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};