1
var generateMatrix = function (n) {
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  const arr = new Array(n).fill(0).map(() => new Array(n).fill(0));
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  let count = 1,
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    index = 1,
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    i = 0,
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    j = 0,
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    changed = false,
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    toIncrease = true;
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  arr[i][j] = index;
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  while (index < n * n) {
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    index++;
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    if (i == n - count && j > count - 1) {
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      j--;
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      toIncrease = false;
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      changed = true;
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    } else if (i !== n - count && j == n - count) {
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      i++;
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      toIncrease = false;
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      changed = true;
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    }
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    if (i == count - 1 && !changed) {
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      if (toIncrease) j++;
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      else j--;
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    } else if (j == count - 1 && !changed) {
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      if (i == count) {
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        toIncrease = true;
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        j++;
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        count++;
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      } else if (toIncrease) i++;
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      else i--;
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    }
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    arr[i][j] = index;
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    if (index == 4 * (n - 1)) {
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      toIncrease = true;
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      count++;
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    }
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    changed = false;
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  }
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  return arr;
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};