Help understanding something please

Question

Im reading through a book that has a word jumble program that I don't understand a part of if anyone can explain.

int main()
{
enum fields {WORD, HINT, NUM_FIELDS};
const int NUM_WORDS = 5;
const string WORDS[NUM_WORDS][NUM_FIELDS] =
{
{"wall", "Do you feel you’re banging your head against something?"},
{"glasses", "These might help you see the answer."},
{"labored", "Going slowly, is it?"},
{"persistent", "Keep at it."},
{"jumble", "It’s what the game is all about."}
};

1. First I don't quite understand what ENUM is?
2. I understand that this is an array made of strings and I understand that Const int num_words=5 means that there are 5 possible words to unscramble. Meaning a 5 row array.
3. I understand that the array is called WORDS. and that it is [num_words] or 5 rows and [num_fields] is the number of columns. But no where does it set the number of columns? Should there not be a num_fields=2;?

Later...
srand(static_cast<unsigned int>(time(0)));
int choice = (rand() % NUM_WORDS);
string theWord = WORDS[choice][WORD]; //word to guess
string theHint = WORDS[choice][HINT]; //hint for word

I understand the 1st two lines. Set a random number with a seed of time and random number is between 0 and 4 based on number of words. but for string theHint=WORDS[choice][HINT] no where was an array with [HINT] established? Where is WORDS[num_words][num_fields]?

This makes no sense to me please help.

Answer 1

Supplemental material for the book I believe you have is linked below....(not everyone knows how to find it/was looking for errata)

Reviewing the source [jumble.cpp in chapter 3] I feel more comfortable answering...

Enums (enumerations...enumerate -- or "number") assign sequential integer values to a list of identifiers (here, CONSTANTS; that's why they're CAPITALIZED) so you can just use the names instead of numbers like 0, 1, 2, etc.

So...automatically:
WORD=0, HINT=1, NUM_FIELDS=2

And...
WORDS[choice][HINT] is the same as writing:
WORDS[choice][1]

but easier to understand for humans.

Book links (source code, data files, etc): Beginning C++ Through Game Programming / Michael Dawson
3rd Edition
http://www.delmarlearning.com/companions/index.asp?isbn=1598633600
4th Edition
http://www.delmarlearning.com/companions/index.asp?isbn=1435457420
5th Edition
http://www.delmarlearning.com/companions/index.asp?isbn=1305109910

Answer 2

thank you kirk