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[wsoxfan1214]

Might be an issue that she has a mac.

That's a rant for a different, day though.

Is there any difference there?

 

[Elfforkusu]

:lol, yes, that's a crucial piece of information. I probably should've asked that first.

You might be able to run it with whatever the Mac version of WINE is, but no guarantees.

 

[fenners]

Might be an issue that she has a mac.

That's a rant for a different, day though.

Is there any difference there?

Visual Studio won't compile anything that runs natively on the mac unless she's running bootcamp + windows...

 

[wsoxfan1214]

Aye. As you can tell, I'm new at this.

I'll see if I can get her to install WINE.

 

[kingslunk]

Aye. As you can tell, I'm new at this.

I'll see if I can get her to install WINE.

Use vim plus g++?

 

[wsoxfan1214]

Use vim plus g++?

What's that...?

Sorry. Haha.

 

[GameplayWhore]

Use vim plus g++?

This would likely also require packaging custom DLLs in a Windows environment.

 

[Slavik81]

I'd bet it would be a lot easier just to port to Java instead.

 

[CrudeDiatribe]

As you can tell, I'm new at this.

Since C++ is compiled, you have to build it with a compiler for the target architecture/OS. Most easily this is done by compiling the source code on the target computer (or one like it). If she's got a Mac, compile your code using g++ on her Mac.

I'll see if I can get her to install WINE.

That's a lot of work.

Why is this even a program and not a document? .html/.doc/.pdf/.txt, etc?

If you want to flex your programming muscles, use an interpreted language that the Mac already has installed, like Perl, Python, PHP, or continue to use a command line program like that and compile the source code on the Mac, won't take long.

Edit: copied your source code verbatim into foo.cpp:

workmac:~ crudediatribe$ g++ foo.cpp 
workmac:~ crudediatribe$ ./a.out 
--------------------------------------------------------------------------------
|                                                                              |
|                                                                              |
|                                                                              |
|                                                                              |
|                                                                              |
|                                                                              |
|                                                                              |
|                                                                              |
|                                                                              |
--------------------------------------------------------------------------------

^C
workmac:~ crudediatribe$

Use vim plus g++?

This would likely also require packaging custom DLLs in a Windows environment.

On the Mac.

 

[TheBez]

#include <iostream>
#include <cstdlib>
#include <cmath>
#include <string>

using namespace std;

int stripWhite(char *str); 


int main()
{
	char str[100];

	
	
	cout << "Enter a sentence and I will delete all spaces in it" << endl;
	cin.getline(str,100);
	int count = stripWhite(str);
	cout << count << " white spaces were removed" << endl;
	cout << "The string without spaces in it is:  " << str << endl;

return 0;
}

int stripWhite(char *str)
{
int i = 0; 
int j = 0;
while(str[i] != '\0')
{
	if(str[i] == ' ')
	j++;
		str[i] = '.' ;
	
	i++;
}

return j;
}

So my assignment is using pointers write a function called stripWhite that will strip all of the white spaces from an array of characters. Your function should return the number of white spaces that you deleted. Your output should look something like the following:

Enter a sentence and I will strip out all spaces.
The quick brown fox jumped over the lazy old dog
Your sentence without spaces is:
Thequickbrownfoxjumpedoverthelazyolddog.

I have that so far which is working to return the number of blank spaces but returning the string as "....................." rather than something proper. Any ideas GAF?

 

[tokkun]

What did you intend this

str[i] = '.' ;

to do? Because it is going to replace every character with '.'

 

[Deleted member 30609]

edit: oh, if the returned number is fine, it's the if block.

 

[TheBez]

What did you intend this

str[i] = '.' ;

to do? Because it is going to replace every character with '.'

Err yes I'm, I don't know what to put in between the ' ' to close the space because my compiler wont simply accept ''

 

[tokkun]

Err yes I'm, I don't know what to put in between the ' ' to close the space because my compiler wont simply accept ''

Yeah, you can't do that in C++. A C string is an array of characters, so you can't just cut one out; you would have to shift down every subsequent character.

I suggest that you don't try to do this in-place - that is, don't use the same string for input and output. Create a 2nd string for output. That should make it easier for you to figure out what to do.

 

[Haly]

'' is not a valid char.

cstrings are tricky to manipulate, you can't just remove a char because you'll need something to fill in the array.

If the sentence looked like:
[q][c][k][ ][r][o][w][n]

You can't just turn it into:
[q][c][k][r][o][w][n]

You'll need to move every char in the word brown one space back, or copy chars from the input into a new array while ignoring all ' ' chars.

 

[Boss Man]

Err yes I'm, I don't know what to put in between the ' ' to close the space because my compiler wont simply accept ''

Think of an array the way Haly posted:

If the sentence looked like:
[q][c][k][ ][r][o][w][n]

Where each [ ] is a place in memory that holds data that we're seeing as characters, like 'q', 'u', or ' '.
The idea of changing one of those values to '', to simply skip that block, is not the correct way to be thinking about an array (nor is it a valid value for a character).


Here's an easy solution without doing anything clever:

Iterate through the array.
Count the blank spaces. (and store the count)


Make a separate array of size (old array size - number of blank spaces).

Iterate through the old array again.
If the character is not a blank space, put it into the other array.
If the character is a blank space, don't put it in the other array.

Your new array is the old string minus blank characters. You can clear out the old array and swap the new one into it.


If you want to avoid creating a new array, you're just going to have to slide the characters over a spot each time you encounter a blank space.

Something like:

for( i=0 ; size-1; i++ )

if( blank space )​

for( j=i; size-2; j++ )​

s[j] = s[j+1]​

I haven't messed with C++ in a little bit, so I don't know if it will complain about any of this or not tbh. You may need to look into the memory allocation functions. I'm assuming that there won't be a problem with 'run-off' spots in the array because the null character is going to be following at the tail, but I dunno.

 

[2real4tv]

Err yes I'm, I don't know what to put in between the ' ' to close the space because my compiler wont simply accept ''

Not sure but wouldn't str = str[i+1] work? And replace null with the last character.

while(str != '\0')
{
if(str == ' ')
j++;
str = str[i+1] ;

i++;
}
str[i-1]='\0';

 

[Slavik81]

Not sure but wouldn't str = str[i+1] work? And replace null with the last character.

No, you need to think about the next time around the loop. It's possible to do this, but +1 is too rigid. The number of steps over you have to take depends on the number of characters removed.

 

[maharg]

void remove_match_in_place(char *str, char match)
{
    for (char *next = str; *next != 0; next++)
    {
        *str = *next;
        if (*next != match) str++;
    }
    *str = 0;
}

Wee.

 

[2real4tv]

No, you need to think about the next time around the loop. It's possible to do this, but +1 is too rigid. The number of steps over you have to take depends on the number of characters removed.

Yes your right. I was always a terrible programmer used alot of trial and error.

 

[Slavik81]

Yes your right. I was always a terrible programmer used alot of trial and error.

You're not alone. Almost everyone's a terrible programmer. That's why we write tests.

 

[Haly]

Wee.

Pointer arithmetic makes my head hurt

 

[2real4tv]

Pointer arithmetic makes my head hurt

Yes it does.

 

[Window]

Are there any specific resources (books or online teaching programs) you guys would recommend for learning C++? It is pretty essential to my degree but I won't get to cover it in my course since I've already progressed past that year and the Uni just recently updated their syllabus which only applies to new students.

 

[maharg]

Are there any specific resources (books or online teaching programs) you guys would recommend for learning C++? It is pretty essential to my degree but I won't get to cover it in my course since I've already progressed past that year and the Uni just recently updated their syllabus which only applies to new students.

Accelerated C++. Ignore all other answers as they are inferior.

 

[Window]

Accelerated C++. Ignore all other answers as they are inferior.

Just to clarify I do know a bit of C, in which case would you still recommend the book? You are referring to this book (http://www.amazon.com/Accelerated-C-Practical-Programming-Example/dp/020170353X correct?

 

[maharg]

Yes and yes. It is even, perhaps, more important that you learn from that book as it avoids treating C++ as an extension of C which is a trap a lot of people familiar with C fall into (and become frustrated by). Accelerated C++ is the canonical introduction to the current best practices of C++, and they're a long way off the language's roots.

 

[Window]

Yes and yes. It is even, perhaps, more important that you learn from that book as it avoids treating C++ as an extension of C which is a trap a lot of people familiar with C fall into (and become frustrated by). Accelerated C++ is the canonical introduction to the current best practices of C++, and they're a long way off the language's roots.

I see. Thanks for that.

 

[Ydahs]

I think I broke C.

For some reason, if I uncomment either one of four unused variables at the beginning of my main method, my programs dies. I can rename them, I can change their values, but removing them causes chaos.

THIS MAKES NO SENSE

 

[Zeppu]

Supply us with code and we'll tell you why.

 

[mugurumakensei]

I think I broke C.

For some reason, if I uncomment either one of four unused variables at the beginning of my main method, my programs dies. I can rename them, I can change their values, but removing them causes chaos.

THIS MAKES NO SENSE

Sounds like your program is writing into memory it shouldn't and uncommenting those variables exacerbated the issue.
Code is necessary for me to verify.

 

[Ydahs]

I was just going to send my lecturer a message but it won't hurt to know why it's happening.

I'll send the code via PM. Can't post it here since it's a University assignment.

 

[usea]

I was just going to send my lecturer a message but it won't hurt to know why it's happening.

I'll send the code via PM. Can't post it here since it's a University assignment.

Lots of people post their university assignments here.

PM it to me too. Not that I will be able to help, but because I'm curious.

 

[Ydahs]

Actually, problem solved!

"Sounds like your program is writing into memory it shouldn't and uncommenting those variables exacerbated the issue."

Spot on. Your comment made me look further done and it turns out there was an uninitialised integer being passed into an accept call for a socket, which led to a bunch of crazy things occurring.

Thanks. Know I feel really stupid for wasting two hours of my life over something so small...

Lots of people post their university assignments here.

PM it to me too. Not that I will be able to help, but because I'm curious.

Our University has a very strict plagiarism policy. Don't want to risk it!

 

[The Technomancer]

Hm, I can't figure out why this code isn't working/compiling:

void Populate(string, vector<string>);

int _tmain(int argc, _TCHAR* argv[])
{
	//population step
	vector<string> Noun;
	Populate("Noun.txt", Noun);

        //stuff

}

void Populate(string Filename, vector<string> &Vector){
	ifstream inFile;
	string BufferString;
	inFile.open(Filename);
	if(!inFile.is_open()){
		cout << "Error: " << Filename << " was not found" << endl;
	}
	while(inFile.good()){
		inFile >> BufferString;
		Vector.push_back(BufferString);
	}
}

Visual Studio says that "more then one instance of the overloaded function Populate matches the argument list".

Any ideas?

 

[Spoo]

Hm, I can't figure out why this code isn't working/compiling:

void Populate(string, vector<string>);

int _tmain(int argc, _TCHAR* argv[])
{
	//population step
	vector<string> Noun;
	Populate("Noun.txt", Noun);

        //stuff

}

void Populate(string Filename, vector<string> &Vector){
	ifstream inFile;
	string BufferString;
	inFile.open(Filename);
	if(!inFile.is_open()){
		cout << "Error: " << Filename << " was not found" << endl;
	}
	while(inFile.good()){
		inFile >> BufferString;
		Vector.push_back(BufferString);
	}
}

Visual Studio says that "more then one instance of the overloaded function Populate matches the argument list".

Any ideas?

Your signature doesn't take a reference but your function implementation does.

Change the top line to read: void Populate(string, vector<string>&);

 

[SolKane]

Got a question here that I'm stuck on. I have to create an array of structures within a class and then initialize them. As I understand it you cannot initialize something within a class definition outside of a structure. But I'm having problems with the syntax. Here's what I've got:

Struct Foo
{
     string s;
     int i;
     double d;

     Foo (string a, int b, double c)
     { 
          s = a;
          i = b;
          d = c;
      }
}

Class Bar
{ 
  public:  
      Foo array[5];
}

int main ()
{
    Bar object;
    object.array =   { Foo("One", 1, 1.0),
                              Foo("Two", 2, 2.0)
                              Foo("Three", 3, 3.0)
                               Foo("Four", 4, 4.0)
                               Foo("Five", 5, 5.0);
}

Is this correct?

 

[Slavik81]

No. Bar needs a constructor that does that initialization in its initializer list.

EDIT: Actually, that's not possible either, since Foo is non-POD. You may have to remove its constructor and use aggregate initialization on it too. This is part of why raw arrays are a pain.

 

[Infinite_Daremo]

Got a question here that I'm stuck on. I have to create an array of structures within a class and then initialize them. As I understand it you cannot initialize something within a class definition outside of a structure. But I'm having problems with the syntax. Here's what I've got:

Struct Foo
{
     string s;
     int i;
     double d;
}

Class Bar
{ 
  public:  
      Foo array[5];
}

int main ()
{
    Bar object;
    object.array =   { { "One", 1, 1.0} ,
                              { "Two", 2, 2.0 } ....;
}

Is this correct?

Try that. Also change string to const char * if that does t work

 

[Slavik81]

Try that. Also change string to const char * if that does t work

That won't work either, unfortunately. The syntax he's using only works at time of initialization. It cannot be used for assignment.

 

[Slavik81]

If you really do want to use aggregate initialization and raw arrays (which are usually more trouble than they're worth... just use std::vector and constructors), definitely give a read through this FAQ on the requirements of aggregate and POD types: http://stackoverflow.com/q/4178175/331041

It doesn't mention too much about aggregate initialization, but it probably is sufficient to say that aggregate initialization can be performed for aggregate types on construction. And only on construction, not on assignment.

 

[Metroid Hunter]

How would one port a code in C++ from Microsoft Visual Studio 2010 to Apple XCode 4?

 

[cpp_is_king]

How would one port a code in C++ from Microsoft Visual Studio 2010 to Apple XCode 4?

Depending on the program, the answer is "with great difficulty".

You're not just porting from one compiler to another, but from one platform to another. Sometimes this is simple, for example if it doesn't use any Windows specific APIs and only uses CRT library, but other times it can be extremely complicated.

I'm not sure if there's a better answer to such a broad question

 

[Infinite_Daremo]

How would one port a code in C++ from Microsoft Visual Studio 2010 to Apple XCode 4?

It all depends. Of you used the win api you're gonna have a bad time

If you used basic c/c++ and the std library it'll be very quick.

 

[wolfmat]

How would one port a code in C++ from Microsoft Visual Studio 2010 to Apple XCode 4?

You make a new project file in XCode, you copy all the source files and assets in, you set compiler options, you treat all errors, you treat all quirks. It usually takes a while, all things considered. Lots of "why is this an error?" -> Google -> Fix. Tenfold that if you have a GUI-heavy application, or one that interfaces with Microsoft products.

 

[wolfmat]

Oh yeah, sometimes, it's better to recode from scratch. So really consider that option. If it's less than 10K lines, I don't see why you wouldn't do it.

 

[Infinite_Daremo]

Oh yeah, sometimes, it's better to recode from scratch. So really consider that option. If it's less than 10K lines, I don't see why you wouldn't do it.

No wai! Hack that shit till its held together with blu-tac and bubble gum.

 

[Slavik81]

It's not very hard to make a cross-platform application if you design for it up-front. Using a cross-platform framework like Qt, it's pretty straight-forward. Though, bolting it on after the fact can potentially be pretty difficult.