string::erase()

igoreshka3333 (2)
Hi guys! Sorry for my Englisg
Faced with such a problem: given a string. It is necessary to put of all the words from a string in the vector, but it does'nt work. I have read this reference
http://www.cplusplus.com/reference/string/string/erase/.
And use 0 and count to clean the string by every iteration.
I think problem in erase(), but who knows?
Thanks!

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  #include <iostream>
#include <string>
#include <vector>
using namespace std;

int main ()
{
    int count = 0;
    string s = "one one one little dog run";
    string word;
    vector<string> v;

    string::iterator iterbeg;
    string::iterator iterend = s.end();
    iterend--;
    for ( iterbeg = s.begin(); iterbeg != s.end(); iterbeg++ )
    {
        ++count;
        if ( *iterbeg == ' ' || *iterbeg == *iterend+1 )
            for ( string::iterator itersec = s.begin(); itersec != iterbeg; itersec++ )
                word += *itersec;
        v.push_back(word);
        word.clear();
        s.erase( 0, count );
    }

    for ( vector<string>::iterator it = v.begin(); it != v.end(); it++ )
        cout << *it << '\n';

    system ("pause");
    return 0;
}
Last edited on
andy1992 (134)
If your string contains a bunch of words in it separated by white spaces then you could use a stream to load them into vector obj

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#include <sstream>

///in main make a stringstream object

 stringstream ss; ss.str (""); ss.clear ();
 //s is your string and v is your vector
 ss <<s; //load string into stream
string temp;

///load words into vector

 while (ss>> temp)
 {
   v.push_back (temp);
 }
Esslercuffi (272)
the for loop at line 20 is causing problems.

first time through, word ends up being a null string, count is 1, so s.erase() call ends up just deleting the first character. problems compound from there.

rather than messing with all these iterators and begin() end() business, consider that strings are actually themselves vectors of characters. This means that you can access them with array subscript notation. Doing so makes this really easy: 
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	for( int c = 0; c < s.size() - 1; c++ )
	{
		if( s[c] == ' ' )
		{
			if( word != "" ) 
				v.push_back( word );
			word = "";
		}
		else
			word += s[c];
	}


*edit* Just noticed that I'm not pushing the last word in the string with the above. fixing it now
Last edited on
Esslercuffi (272)
here's the fixed version 
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	for( int c = 0; c < s.size(); c++ )
	{
		if( s[c] == ' ' )
		{
			if( word != "" ) 
				v.push_back( word );
			word = "";
		}
		else
			word += s[c];
	}
	if( word != "" ) 
		v.push_back( word );


stringstreaming it like Andy suggested above might be the way to go though.
Last edited on
igoreshka3333 (2)
Thanks a lot for your answers! Problem is fixed
andy1992, interesting approach, I will study!
Esslercuffi, really every symbol were deleted for each iteration, I forgot the brackets in the operator if !
Last edited on
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