Need study help : /

Some of the questions on our study guide are really vauge and im not sure how to answer them. I dont want answers, jus a nudge in the right directions.

6) Are there segments of code that must be defined above all others? yes of course...but thats alot of things If so, which ones? umm...yea...

23) Explain the empty for loop (;;) :

Gee if she ever taught that i might be able too.....

24) Name the parts of a C++ program:

Want a book?

56) Explain why and when to use a continue statement:

Wow, i dont think she payed attention in class cuz she never taught that one either

For first, whats first thing you define in a program.
for second repost with diabled smillies :D
Third i duno

1) typically pre-processor directives

2) Explain the empty for loop (; :)

>typically pre-processor directives

well, when you #include<iostream>, you're defining cout (along with alot of other things), so Iamien is still right...

> Are there segments of code that must be defined above all others?

what happens if you define a function after main without a prototype?

>Explain why and when to use a continue statement

your in a loop that does stuff. at some iteration you realize "crap, i dont want to do stuff this iteration" using 'continue' basically jumps to the bottom of the loop, skipping the code. the loop then moves on to its next iteration. did that make sense? heres an example

Code:

---

for(int i = 0; i < MAX; i++)
{
      if( (i % 2) == 0 )
          continue;

      cout << i << ", ";
}

---

output:

1, 3, 5, 7, ...

Quote:

---

Originally posted by major_small
>typically pre-processor directives

well, when you #include<iostream>, you're defining cout (along with alot of other things), so Iamien is still right...

---

umm its the same thing. I said pre-processor directives, header files ARE PP-directives...and they arent' always the first thing. Pragma comments sometimes come first, for example.

Thanks perspective.

have you really never used a continue statement? i thought someone like you would have already....

its just where you skip to the end of a loop

no, to be dead honest i had never even heard of it till the other day, i guess i just missed it? Thanks for the info guys.

Quote:

---

Originally posted by RoD
umm its the same thing. I said pre-processor directives, header files ARE PP-directives...and they arent' always the first thing. Pragma comments sometimes come first, for example.

Thanks perspective.

---

that's exactly what I said... try reading the post...


question: how far can break; and continue; go? do they just go to the nearest loop? or do they go one level up... i.e. if they're in a nested IF, do they stop the IF containing the IF they're in?

empty for loop is basically to have a controlled infinitive loop...

for the parts of a c++ program, how advanced is this class? by the looks of it, its pretty basic, so i'd just go with function prototypes, main, and function declarations

Quote:

---

Originally posted by major_small
question: how far can break; and continue; go? do they just go to the nearest loop? or do they go one level up... i.e. if they're in a nested IF, do they stop the IF containing the IF they're in?

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breaks have to be within a loop or a switch statement, and will immediately terminate the loop, and continues have to be in a loop, where they immediately jump to the bottom of the loop.

Quote:

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Originally posted by Zach L.
breaks have to be within a loop or a switch statement, and will immediately terminate the loop, and continues have to be in a loop, where they immediately jump to the bottom of the loop.

---

oh okay... thanks alot... i got confused because of the breaks in the switch statement...

I might use an empty for-loop is there is more than one condition that causes an exit ("break") from the loop. Or, when the exit condition needs to be tested in the middle of the loop.

Or maybe you want to exit the loop (and the function) with a "return"... maybe multiple returns depending on various conditions.

Actually, when I want an infinite loop... I think I've used while(1) or do-while(1)

ok here is how i answered some questions, and a few new ones, test is tommorow before i go before the board:

>>Name the parts of a C++ program

Pre-processor directives, prototypes, data types, classes. functions,array's, sorts, etc

>>Explain the empty for loop

The counter is declared and initialized outside of the loop condition but referenced in conditional statements within the loop.

int i = 0;

for (; i < 5; i++)
{
....
}


New Question:

98) List the data types and number of bytes each:

I have NO idea what the bytes are, but i listed char, int, double, float, bool, and string cuz we did those.

New Question:

101) Show code line to associate a txt file to outfile variable using append attribute:

Ok i get this much:

ofstream outfile;
outfile.open("c:\\blah.txt");

but whats the append attribute? Append is add to something right?

Thanks guys i owe you....

Quote:

---

Originally posted by RoD
>>Explain the empty for loop

The counter is declared and initialized outside of the loop condition but referenced in conditional statements within the loop.

int i = 0;

for (; i < 5; i++)
{
....
}


New Question:

98) List the data types and number of bytes each:

I have NO idea what the bytes are, but i listed char, int, double, float, bool, and string cuz we did those.

New Question:

101) Show code line to associate a txt file to outfile variable using append attribute:

Ok i get this much:

ofstream outfile;
outfile.open("c:\\blah.txt");

but whats the append attribute? Append is add to something right?

Thanks guys i owe you....

---

Empty loops are the same think as infinite loops. This is an example: for(;;)

99) This is system dependent. Use cout<<sizeof(datatype); where datatype is the datatype you want to find the size of.

101) Append means that the outputted text is added to the end of the the file. Check out this link.

thnx man, i am really going to enjoy the system dependant answer, seriously i cant wait till she marks it wrong.

Quote:

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>>Explain the empty for loop

The counter is declared and initialized outside of the loop condition but referenced in conditional statements within the loop.

---

Wrong!!
"Empty" refers to the loop body. It just means that all the "action" is inside the parentheses. An example is:

Code:

---

for( d=2; d < n && n / d != 0; d++ ) ;  // exits loop when d is a divisor of n (or d==n)

---

Some people prefer this style:

Code:

---

for( d=2; d < n && n / d != 0; d++ )
    ;

---

or this:

Code:

---

for( d=2; d < n && n / d != 0; d++ )
    {};

---

to make it clear that it's not just a mistake.

Another name for this is a Null Statement.

are you sure she's not looking for a relativity answer? as in:

unsigned<float<double

golfinguy4:

Are you sure? I've only seen for(;;); referred to as an infinite loop, same as while(1);

RoD:
Your post wasn't clear. Did teacher give for(;;) as an example?

well i asked bout it today and i posted what she said she wanted.

Code:

---

int i = 0;

for (; i < 5; i++)
{
cout << "Runs 5 times!" << endl;
}

---

that just means the LCV is initialized outside the loop...

Quote:

---

98) List the data types and number of bytes each:

I have NO idea what the bytes are, but i listed char, int, double, float, bool, and string cuz we did those.

---

Missed a couple there... Off the top of my head,

char, int, short, long (each of which comes in signed and unsigned flavors)
bool, float, double, long double

ya i only listed the ones she actually went over, cs2 sux for us

Well, I don't see how she can call that an empty anything. It's not empty. I see examples like the one I posted and examples like the one golfinguy posted both being called empty loops. They both make sense. I don't see any that look like your teacher's.

But she's marking the test. Too bad. Maybe you can ask her again, & show her our examples, before the test.

Good luck.

Yeah, I'd say Stiltskin's is probably the most correct definition of empty loop... golfinguy's is probably technically an infinite loop, and not empty.

Also, on the structure of a program, I'd put something like this (in no particular order):

Pre-processor
Global-Scope/Namespace-Scope Constants (If your teacher is really picky, I suppose typedefs would go here too)
Function Prototypes
Class Declarations
Class Definitions
Driver (i.e. main)

Yeah, my empty loop was wrong. I misread what he wanted.

well the test is in a few hours, and thnx to you guys im sure i'll pass it, thank ya.

good luck ;-)

110 question study guide, TWO questions on the actual test. god i really hate that $$$$$

And the real test was to see if you could keep your sanity after all that. ;)

what were the questions?

the append and one with a switch statement that i didnt need to post