How many levels of nesting must be supported by a computer ?

[TILLI]

(according to ANSI specifications)

[Banfa]

How many levels of nesting what?

[TILLI]

Don't know. This was the only question. Perhaps of nested if .Is there any minimum number?
Anyways the options are: 10, 15, 25, 30, none of these.

[RedSon]

It's impossible to answer that question. There is no subject in that sentence. It's like asking the question: "How many cups are in a recipe according to Better Homes and Gardens?"

How many cups of what are in what recipe? It's unanswerable.

[donbock]

Refer to C99 section 5.2.4.1 (Environmental Limits: Translation limits). This tells us that a conforming implementation must be able to translate and execute a program containing at least one instance of the following nesting-level related limits:

• 127 nesting levels of blocks
• 63 nesting levels of conditional inclusion
• 63 nesting levels of parenthesized declarators within a full declarator
• 63 nesting levels of parenthesized expressions within a full expression
• 15 nesting levels for #included files
• 63 levels of nested structure or union definitions in a single struct-declaration-list
• (Perhaps other limits that I didn't see when I skimmed C99 for this post.)

So it is clear that Banfa and RedSon are right -- the answer depends on just what it is that you're trying to nest.