`Worksheet.isCellInMergedRanges` make write slow.

[jilen]

For example 10000 rows x 20 cols x 100 merged regions There could be 10_000_000 Worksheet.isCellInMergedRanges iterations.

[jilen]

Possible solution:

• Just treat cells in merged region as normal cell while calc width
• Use some data structure like r-tree instead of set.

[ochedru]

Thanks for your feedback. Indeed, we could use a better data structure for mergedRanges or rethink column width computation, which is not perfect anyway.