Maximum Non Negative Product in a Matrix LeetCode solution in JavaScript

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var maxProductPath = function (grid) {
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  const R = grid.length,
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    C = grid[0].length;
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  if (R === 0 || C === 0) return -1;
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  const mat = [...Array(R)].map(() => [...Array(C)].map(() => new Array(2)));
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  mat[0][0] = [grid[0][0], grid[0][0]];
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  for (let i = 1; i < R; i++)
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    mat[i][0] = [mat[i - 1][0][0] * grid[i][0], mat[i - 1][0][1] * grid[i][0]];
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  for (let i = 1; i < C; i++)
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    mat[0][i] = [mat[0][i - 1][0] * grid[0][i], mat[0][i - 1][1] * grid[0][i]];
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  for (let i = 1; i < R; i++) {
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    for (let j = 1; j < C; j++) {
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      const max = Math.max(mat[i - 1][j][0], mat[i][j - 1][0]),
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        min = Math.min(mat[i - 1][j][1], mat[i][j - 1][1]);
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      if (grid[i][j] >= 0) mat[i][j] = [max * grid[i][j], min * grid[i][j]];
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      else mat[i][j] = [min * grid[i][j], max * grid[i][j]];
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    }
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  }
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  return mat[R - 1][C - 1][0] >= 0 ? mat[R - 1][C - 1][0] % (10 ** 9 + 7) : -1;
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};