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by dang 3990 days ago
> the main problem is that you cant's nest 3 for loops

I'm curious what you mean by this. Care to explain?

2 comments

The problem is that the spreadsheets are 2D, so you iterate easily over two variables, the row and the column.

If you need to "program" this in an Excel spreadsheet

  For i = 1 to 5
    For j = 1 to 5
      If 2 * i + j = i * j then
        Print i, j, "*"
      End If
    Next
  Next
You can "write" this in a 6x6 block with the values

    1  2  3  4  5
  1 =If(2*B$1+$A2=B$1*$A2, "*", "")
  2
  3
  4
  5 
And copy the formula from B2 to all the cells, so you get

    1  2  3  4  5
  1 
  2
  3       *
  4    *
  5
Ah, that's what I thought you might mean. Can you talk about why you use spreadsheets in the first place, then? You're dealing with nontrivial problems if you hit this limitation, and you could write programs in a general-purpose language if you wanted to. So what do you get from Excel?

(I care about this, btw, because my real job is making a new spreadsheet.)

I don't know what the limit for `for` loops is, but Excel has some limits to nesting of flow control structures like `if`. For example, you cannot nest `if` statements more than seven deep. I suspect the parent poster is referring to a limitation similar to this, but for nesting `for` loops.