Matrix Cells in Distance Order LeetCode solution in JavaScript

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var allCellsDistOrder = function (rows, cols, rCenter, cCenter) {
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  let distances = [];
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  let result = [];
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  //create a new "visited" cells matrix
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  let visited = new Array(rows).fill([]);
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  for (i = 0; i < visited.length; i++) {
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    visited[i] = new Array(cols).fill(0);
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  }
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  const computeDistances = (row, col, rCenter, cCenter) => {
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    if (row >= rows || col >= cols) return;
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    if (visited[row][col]) return; // don't compute distance again if cell already visited
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    visited[row][col] = 1;
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    let distance = Math.abs(rCenter - row) + Math.abs(cCenter - col);
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    if (distances[distance]) {
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      distances[distance].add([row, col]);
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    } else {
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      distances[distance] = new Set();
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      distances[distance].add([row, col]);
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    }
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    computeDistances(row + 1, col, rCenter, cCenter);
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    computeDistances(row, col + 1, rCenter, cCenter);
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  };
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  computeDistances(0, 0, rCenter, cCenter);
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  distances.forEach((distance) => {
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    result.push(...distance);
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  });
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  return result;
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};