Do you see something wrong here?

[scout51]

PLease can you tell me what is wrong here?
Thanks

#include <iostream>

using namespace std;

void main()
{
int number, count, total;
total = 0;
count = 0;

cout << "Enter a number less than 10" << endl;
cin >> number;

while(count < number )
{
total = total + number;
count++;
}
//end while

system("pause");
}

[Cubbi]

1. main() cannot return void

2. it's poor style creating variables before they are needed

3. endl is redundant before cin >>

4. the code after cin >> number and before system("pause") does not affect the program output and will be eliminated by the compiler

5. the system command "pause" does not exist on many platforms.

[scout51]

Could you please tell me why (your 4th statement) will be eliminated by the compiler?
Thanks in advance

[jorz]

Hi Scout,

I don't think it will but I can be wrong.

put a cout << "test" << number << endl;
in your while loop and you will find out

watch while loops they have to be implemented very well or your will end up in a endless loop it is better to use a for loop in those cases.

[gurukrupa]

I think you are making table of entered number
so just print the number in the while loop...

[lwtan90]

Please drop

system("PAUSE");

replace it with

return 1;

[lwtan90]

Agree with gurukrupa, you forgot to print out your result.

What I feel about your program is that:

I was hungry.
I bought my food, but I did not eat it.
I found myself still hungry.

Apply to your code:
You are trying out while loop.
You coded the while loop, but I did not print out the numbers that shows while loop is working.
You thought that while loop was wrong.

=p

Just joking.

[zb0S216C]

scout51 wrote:

"Could you please tell me why (your 4th statement) will be eliminated by the compiler?"

Because total and count do not affect the program (no noticeable side-effects). Therefore, the compiler will see it as a waste of processing time, and will optimise it away. However, if you used total and count in a way that affects the program (such as opening a file, writing to the output buffer, or using it to store input), the compiler cannot ignore that and the code will remain (optimising away the code would break the program).

_Wazzak

[vlad from moscow]

Too many lines of code that to calculate number * number. And moreover even this simple operation the program does incorrectly because if the number will be enetered as negative the sum will be equal to zero.:)

[Wolman]

The loop has no function. It does not output the numbers or the result of the calculation.

Secondly, what is the program supposed to do?

total = total + number will give you a multiple of whatever number is. If number is 5 total will be (counter:total) 0:5 1:10 2:15 3:20 4:25. The value of number does not change in the loop.

If you are trying to total up the values untill you get to number for instance 1+2+3+4....number then it should be total = total + counter.

to see the effect put cout >> total in the loop after the calculation.

[vlad from moscow]

@Wolman

to see the effect put cout >> total in the loop after the calculation.

This is only if you mean that the effect is some sort of compilation error.:)

[chipp]

it's poor style creating variables before they are needed

i don't understand, i don't see variables are created before they are needed... what i saw, is the variable creation is done exactly when they needed...

[zb0S216C]

@chipp: The declaration of both total & count could easily be postponed until they are actually referenced.

_Wazzak

[chipp]

so it should be:

int number = 0;

cout << "Enter a number less than 10" << endl;
cin >> number;

int total = 0, count = 0;

like that?

[zb0S216C]

More or less, but number could be declared after the std::cout statement.

_Wazzak

[vlad from moscow]

It would be much better to write

for ( int i = 0; i < number; i++ ) total += number;
instead of

while(count < number )
 {
 total = total + number;
 count++;
 }