boost string split to eliminate spaces in words

Question

I have written this code to split up a string containing words with many spaces and/or tab into a string vector just containing the words.

#include<iostream>       
#include<vector>                        
#include<boost/algorithm/string/split.hpp>       
#include<boost/algorithm/string.hpp>                         
int main()                              
{                  
    using namespace std;                                     

    string str("cONtainS            SoMe    CApiTaL WORDS");       

    vector<string> strVec;              
    using boost::is_any_of;       

    boost::algorithm::split(strVec, str, is_any_of("\t "));       

    vector<string>::iterator i ;       

    for(i = strVec.begin() ; i != strVec.end(); i++)       
        cout<<*i<<endl;              

    return 0;                                             
}

I was expecting an output

cONtainS
SoMe
CApiTaL
WORDS

but i m geting output with space as an element in the strVec i.e

cONtainS











SoMe



CApiTaL
WORDS

Solution 1

You need to add a final parameter with the value boost::token_compress_on, as per the documentation:

boost::algorithm::split(strVec,str,is_any_of("\t "),boost::token_compress_on); 

Solution 2

It's because your input contains consecutive separators. By default split interprets that to mean they have empty strings between them.

To get the output you expected, you need to specify the optional eCompress parameter, with value token_compress_on.

http://www.boost.org/doc/libs/1_43_0/doc/html/boost/algorithm/split_id667600.html