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var spiralMatrixIII = function (rows, cols, rStart, cStart) {
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  let output = [];
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  let r = rStart,
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    c = cStart;
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  let right = true,
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    down = false,
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    left = false,
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    up = false;
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  let steps = 1,
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    maxSteps = 2;
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  while (output.length !== rows * cols) {
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    if (r >= 0 && c >= 0 && r < rows && c < cols) output.push([r, c]);
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    if (right) {
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      if (steps + 1 > maxSteps) {
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        (steps = 2), r++;
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        (right = false), (down = true);
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      } else c++, steps++;
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    } else if (down) {
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      if (steps + 1 > maxSteps) {
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        (steps = 2), c--;
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        (down = false), (left = true);
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        maxSteps++;
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      } else r++, steps++;
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    } else if (left) {
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      if (steps + 1 > maxSteps) {
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        (steps = 2), r--;
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        (left = false), (up = true);
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      } else c--, steps++;
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    } else if (up) {
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      if (steps + 1 > maxSteps) {
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        (steps = 2), c++;
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        (up = false), (right = true);
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        maxSteps++;
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      } else r--, steps++;
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    }
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  }
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  return output;
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};