On: How Effective are Technical Interviews?

[varjag]

Well, itoa() stands for "integer to ASCII". You can use the property of sequential numbers (starting at 0x30 in ASCII table) to avoid the case statement.

[fendale → varjag]

Good point, I actually thought of doing that and then dismissed it. Maybe the best perfoming way would be to use the remainder as the index to an array (suggested in another comment)?

[varjag → fendale]

It's C we talking about, just add the remainder to 0x30 and you get your character.

[Someone → varjag]

[pedantic]: you should use '0', not 0x30.

1. The standard library C function atoi may be named 'ASCII to integer', but it should convert a numerical string in the platform's encoding to integer. For symmetry, itoa should convert an integer to a platform encoded numeric string, not to an ASCII numerical string.

2. Not all computers use ASCII for C strings. Because of that, '0' need not equal 0x30. For example, in EBCDIC, one has '0' == 0xF0.

Utterly pedantic: IIRC, the C standard guarantees that '0' through '9' are contiguous and in order. If you know better, or aren't sure, use "0123456789"[i] to convert a 0...9 value to the corresponding char.

[varjag → Someone]

I used 0x30 for didactic purposes, so that a person less familiar with C would understand what exactly is happening.