cstring

i have a string that has various sized spaces between the words, (e.g the big brown fox jumps over the fence.)
i am trying to assign each of the words to an array and then rejoin the array of words without the spaces. is this easy?
i have also been advised to use strcmp. but i am not sure how this would work.

help would be great.

Pretty easy using string streams. You would not even need an array as you can join the words back by concatenating to the result string.

Quote:

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is this easy?

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That's up to you to decide:

Code:

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const char* cstr = "hello    world goodbye  world";

string str(cstr);  //cstring-->c++ string
istringstream input(str); //creates a container called 'input', which
                          //you can read from like a file

string result="";
string current = "";

while(input>>current)  //read from input as if it were a file
{                      //the >> operator skips leading whitespace until it finds a character,
                        //then it stops reading as soon as it encounters trailing whitespace

        result += current;
}

cout<<result<<endl;  //helloworldgoodbyeworld

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ok. that makes sense. here is my code so far. i am missing something pretty basic.

Code:

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#include <iostream>
#include <fstream>
#include <string>

using std::cout;
using std::endl;
using std::cerr;
using std::string;
using std::getline;

int main ()
{
  string myStringErrors;

  std::ifstream file("Lab1.txt");
 
  if (!file)
    {
    cerr<<"Can't open file"<<endl;
    return EXIT_FAILURE;
    }
 //read file one line at a time
  while (std::getline(file,myStringErrors))
    {
    //do stuff with line
    cout<<myStringErrors<<endl;

        const char* myStringNoSpaces = myStringErrors;

        string str(myStringNoSpaces);                //cstring-->c++ string
        istringstream input(str);                        //creates a container called 'input', which
                                                                                //you can read from like a file
        string result="";
        string current = "";

        while(input>>current)                                //read from input as if it were a file
        {                                                                        //the >> operator skips leading whitespace
        result += current;
        }

        cout<<result<<endl;
        }
  cout<<endl;
}

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when i compile i always get an error message saying : cannot convert from 'std::string' to 'const char *'. how do i change my std::string? can i change my std::string to suit?

Whenever you ask a question about an error, ALWAYS post a message on the line that has the error, like this:

Code:

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int n = 10.5;  //***ERROR***

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Or, post the error message along with the line of code:

Quote:

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error message saying : cannot convert from 'std::string' to 'const char *'.
which is this line of code:

int n = 10.5;

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You can't assign a string type to a variable that is of type const char*. This code makes no sense:

Code:

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string myStringErrors;
...
const char* myStringNoSpaces = myStringErrors;
string str(myStringNoSpaces)

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You try to convert myStringErrors from a string type to a const char*. Then you convert the result back to a string type. Hello? You had a string type to start with.

as i am sure you can tell i am new to programming and it is definately not my strong point. i was told that to eliminate spaces i should use 'strcmp' (not sure how that is going to help) or to assign my string to an array. the string 'myStringErrors' is from a file that was given to me. this i managed to open after hours of trying. but once opend i was told to assign each individual word to an array and then rejoin the array without the spaces. i have been sitting for hours doing this. no luck. also thought that maybe 'strcpy' with a loop using string::replace (' ', ' ') will any of these work or am i wasting my time?

thank you for the tips on error message posting. much appreciated

Well suppose your code did this:

int num = 10;
int irrelevant = num;
num = irrelevant;

What would you do to make that code more efficient?

not sure. sorry. do you need both variables? if not: int num = 10;.

Ok, now apply that same logic to this code:

Code:

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string myStringErrors;
...
std::getline(file,myStringErrors)
...
const char* myStringNoSpaces = myStringErrors;
string str(myStringNoSpaces);
istringstream input(str);

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sorry. get what you mean now. will have a look. this is frustrationg me now. need a break i think.