Word count in c++ after using (getline(cin,input))?

Question

So i am extremely new to this. I have an assignment to count the number of lines, words, characters, unique lines and unique words from user input. So far I have gotten lines, unique lines and characters from my code. I thought I got the words but then it doesn't work when i factor in double spaces and tabs. Also i have no clue how to find the unique words. Please offer your assistance.

Code:

 // What I dont have:
//words
//Total words


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


unsigned long countWords(const string& s, set<string>& wl);  //total words

int main()
{
     int linenum=0, charnum=0, totalwords=0;
     set<string> lines;
     string input;
     set<string> unique;   //to store unique words from countWords function

while (getline(cin,input))
    {
         lines.insert(input);
         linenum++; 

         charnum+= input.length();


         totalwords += countWords(input,unique);        
    }

    cout << linenum <<"     "<< totalwords <<"     "<< charnum <<"     " << lines.size()<<"     "         << unique.size()<< endl;

         system("PAUSE"); 
     return 0;
}

unsigned long countWords(const string& s, set<string>& wl) //total words        
{
     int wcount=1;         


     for (unsigned int i=0; i < s.length(); i++)
     {   

          if ((s.at(i) == ' ')&&(s.at(i)+1 !='\0')) {
                         wcount++;

                         }

      }    


return wcount;
}

Answer 1

Here is an example of how the function could look

#include <iostream>
#include <sstream>
#include <set>
#include <string>
#include <iterator>
#include <algorithm>


unsigned long countWords( std::set<string> &wl, const std::string &s )  
{
    std::istringstream is( s );
    wl.insert( std::istream_iterator<std::string>( is ),
               std::istream_iterator<std::string>() );

    is.clear();
    is.str( s );

    return ( std::distance( std::istream_iterator<std::string>( is ),
                            std::istream_iterator<std::string>() ) );
}

//...

In this example puctuations are considered as parts of words.

If you do not know yet std::istringstream and other facilities of C++ then you can write the function the following way

#include <iostream>
#include <set>
#include <string>


unsigned long countWords( std::set<string> &wl, const std::string &s )  
{
    const char *white_space = " \t";
    unsigned long count = 0;

    for ( std::string::size_type pos = 0, n = 0; 
          ( pos = s.find_first_not_of( white_space, pos ) ) != std::string::npos;
          pos = n == std::string::npos ? s.size() : n )
    {
        ++count;
        n = s.find_first_of( white_space, pos );
        wl.insert( s.substr( pos, ( n == std::string::npos ? std::string::npos : n - pos ) ) );
    }

    return count;
}

//...

Answer 2

you need to put +1 inside brackets,your function will be like that

unsigned long countWords(const string& s, set<string>& wl) //total words        
{
     int wcount=0;// initial value must be zero
     int N = 0;// you need to add this to count the characters of each word.
     for (unsigned int i=0; i < s.length(); i++)
     {   
          if ((s.at(i) == ' ')||(s.at(i+1) =='\0')) {// Condition must be or instead of and
                 wl.insert(s.substr(i-N-1,N));
                 ++wcount;
                 N = 0;
              }else ++N;

      }    
return wcount;
}